diff --git a/editor/composer/src/nsComposerCommands.cpp b/editor/composer/src/nsComposerCommands.cpp
index ba8813f44f7..3ecb300fe2b 100644
--- a/editor/composer/src/nsComposerCommands.cpp
+++ b/editor/composer/src/nsComposerCommands.cpp
@@ -317,7 +317,7 @@ nsListCommand::GetCurrentState(nsIEditor *aEditor, const char* aTagName,
   PRBool bMixed;
   PRUnichar *tagStr;
   nsresult rv = GetListState(aEditor,&bMixed, &tagStr);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // Need to use mTagName????
   PRBool inList = (0 == nsCRT::strcmp(tagStr,
@@ -380,7 +380,7 @@ nsListItemCommand::GetCurrentState(nsIEditor *aEditor, const char* aTagName,
 
   PRBool bMixed, bLI, bDT, bDD;
   nsresult rv = htmlEditor->GetListItemState(&bMixed, &bLI, &bDT, &bDD);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   PRBool inList = PR_FALSE;
   if (!bMixed)
@@ -414,7 +414,7 @@ nsListItemCommand::ToggleState(nsIEditor *aEditor, const char* aTagName)
   rv = params->GetBooleanValue(STATE_ALL,&inList);
   if (NS_FAILED(rv)) 
     return rv;
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   if (inList)
   {
@@ -422,7 +422,7 @@ nsListItemCommand::ToggleState(nsIEditor *aEditor, const char* aTagName)
     PRBool bMixed;
     PRUnichar *tagStr;
     rv = GetListState(aEditor,&bMixed, &tagStr);
-    if (NS_FAILED(rv)) return rv; 
+    NS_ENSURE_SUCCESS(rv, rv); 
     if (tagStr)
     {
       if (!bMixed)
@@ -461,7 +461,7 @@ nsRemoveListCommand::IsCommandEnabled(const char * aCommandName,
     PRBool bMixed;
     PRUnichar *tagStr;
     nsresult rv = GetListState(editor, &bMixed, &tagStr);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
 
     *outCmdEnabled = bMixed ? PR_TRUE : (tagStr && *tagStr);
     
@@ -816,7 +816,7 @@ nsFontSizeStateCommand::GetCurrentState(nsIEditor *aEditor,
                                          EmptyString(),
                                          &firstHas, &anyHas, &allHas,
                                          outStateString);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCAutoString tOutStateString;
   tOutStateString.AssignWithConversion(outStateString);
@@ -851,15 +851,15 @@ nsFontSizeStateCommand::SetState(nsIEditor *aEditor, nsString& newState)
       newState.EqualsLiteral("medium")) {
     // remove any existing font size, big or small
     rv = htmlEditor->RemoveInlineProperty(fontAtom, NS_LITERAL_STRING("size"));  
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
 
     nsCOMPtr<nsIAtom> bigAtom = do_GetAtom("big");
     rv = htmlEditor->RemoveInlineProperty(bigAtom, EmptyString());  
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
 
     nsCOMPtr<nsIAtom> smallAtom = do_GetAtom("small");
     rv = htmlEditor->RemoveInlineProperty(smallAtom, EmptyString());  
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   } else {
     // set the size
     rv = htmlEditor->SetInlineProperty(fontAtom, NS_LITERAL_STRING("size"),
@@ -1150,7 +1150,7 @@ nsAbsolutePositioningCommand::ToggleState(nsIEditor *aEditor, const char* aTagNa
 
   nsCOMPtr<nsIDOMElement>  elt;
   nsresult rv = htmlEditor->GetAbsolutelyPositionedSelectionContainer(getter_AddRefs(elt));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   if (elt) {
     // we have to remove positioning on an element
@@ -1185,7 +1185,7 @@ nsDecreaseZIndexCommand::IsCommandEnabled(const char * aCommandName,
   if (positionedElement) {
     PRInt32 z;
     nsresult res = htmlEditor->GetElementZIndex(positionedElement, &z);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     *outCmdEnabled = (z > 0);
   }
 
diff --git a/editor/composer/src/nsComposerCommandsUpdater.cpp b/editor/composer/src/nsComposerCommandsUpdater.cpp
index 5f814d1e05f..b034083e259 100644
--- a/editor/composer/src/nsComposerCommandsUpdater.cpp
+++ b/editor/composer/src/nsComposerCommandsUpdater.cpp
@@ -262,7 +262,7 @@ nsComposerCommandsUpdater::PrimeUpdateTimer()
   {
     nsresult rv = NS_OK;
     mUpdateTimer = do_CreateInstance("@mozilla.org/timer;1", &rv);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
 
   const PRUint32 kUpdateTimerDelay = 150;
diff --git a/editor/composer/src/nsComposerDocumentCommands.cpp b/editor/composer/src/nsComposerDocumentCommands.cpp
index 6d301d758af..bab1c06079d 100644
--- a/editor/composer/src/nsComposerDocumentCommands.cpp
+++ b/editor/composer/src/nsComposerDocumentCommands.cpp
@@ -76,7 +76,7 @@ GetPresContextFromEditor(nsIEditor *aEditor, nsPresContext **aResult)
 
   nsCOMPtr<nsISelectionController> selCon;
   nsresult rv = aEditor->GetSelectionController(getter_AddRefs(selCon));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!selCon) return NS_ERROR_FAILURE;
 
   nsCOMPtr<nsIPresShell> presShell = do_QueryInterface(selCon);
@@ -116,7 +116,7 @@ nsSetDocumentOptionsCommand::DoCommandParams(const char *aCommandName,
 
   nsRefPtr<nsPresContext> presContext;
   nsresult rv = GetPresContextFromEditor(editor, getter_AddRefs(presContext));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!presContext) return NS_ERROR_FAILURE;
 
   PRInt32 animationMode; 
@@ -136,11 +136,11 @@ nsSetDocumentOptionsCommand::DoCommandParams(const char *aCommandName,
     if (!container) return NS_ERROR_FAILURE;
 
     nsCOMPtr<nsIDocShell> docShell(do_QueryInterface(container, &rv));
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
     if (!docShell) return NS_ERROR_FAILURE;
 
     rv = docShell->SetAllowPlugins(allowPlugins);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
 
   return NS_OK;
@@ -167,7 +167,7 @@ nsSetDocumentOptionsCommand::GetCommandStateParams(const char *aCommandName,
   // get pres context
   nsRefPtr<nsPresContext> presContext;
   rv = GetPresContextFromEditor(editor, getter_AddRefs(presContext));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!presContext) return NS_ERROR_FAILURE;
 
   PRInt32 animationMode;
@@ -178,7 +178,7 @@ nsSetDocumentOptionsCommand::GetCommandStateParams(const char *aCommandName,
     // http://lxr.mozilla.org/seamonkey/source/modules/libpr0n/public/imgIContainer.idl
     rv = aParams->SetLongValue("imageAnimation",
                                presContext->ImageAnimationMode());
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
 
   PRBool allowPlugins; 
@@ -189,14 +189,14 @@ nsSetDocumentOptionsCommand::GetCommandStateParams(const char *aCommandName,
     if (!container) return NS_ERROR_FAILURE;
 
     nsCOMPtr<nsIDocShell> docShell(do_QueryInterface(container, &rv));
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
     if (!docShell) return NS_ERROR_FAILURE;
 
     rv = docShell->GetAllowPlugins(&allowPlugins);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
 
     rv = aParams->SetBooleanValue("plugins", allowPlugins);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
 
   return NS_OK;
diff --git a/editor/composer/src/nsComposerRegistration.cpp b/editor/composer/src/nsComposerRegistration.cpp
index 3b5c2b311e9..f9c9378f08a 100644
--- a/editor/composer/src/nsComposerRegistration.cpp
+++ b/editor/composer/src/nsComposerRegistration.cpp
@@ -126,19 +126,19 @@ CreateControllerWithSingletonCommandTable(const nsCID& inCommandTableCID, nsICon
 {
   nsresult rv;
   nsCOMPtr<nsIController> controller = do_CreateInstance("@mozilla.org/embedcomp/base-command-controller;1", &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsIControllerCommandTable> composerCommandTable = do_GetService(inCommandTableCID, &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   // this guy is a singleton, so make it immutable
   composerCommandTable->MakeImmutable();
   
   nsCOMPtr<nsIControllerContext> controllerContext = do_QueryInterface(controller, &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   rv = controllerContext->Init(composerCommandTable);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   *aResult = controller;
   NS_ADDREF(*aResult);
@@ -154,7 +154,7 @@ nsHTMLEditorDocStateControllerConstructor(nsISupports *aOuter, REFNSIID aIID,
 {
   nsCOMPtr<nsIController> controller;
   nsresult rv = CreateControllerWithSingletonCommandTable(kHTMLEditorDocStateCommandTableCID, getter_AddRefs(controller));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   return controller->QueryInterface(aIID, aResult);
 }
@@ -166,7 +166,7 @@ nsHTMLEditorControllerConstructor(nsISupports *aOuter, REFNSIID aIID, void **aRe
 {
   nsCOMPtr<nsIController> controller;
   nsresult rv = CreateControllerWithSingletonCommandTable(kHTMLEditorCommandTableCID, getter_AddRefs(controller));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   return controller->QueryInterface(aIID, aResult);
 }
@@ -179,10 +179,10 @@ nsHTMLEditorCommandTableConstructor(nsISupports *aOuter, REFNSIID aIID,
   nsresult rv;
   nsCOMPtr<nsIControllerCommandTable> commandTable =
       do_CreateInstance(NS_CONTROLLERCOMMANDTABLE_CONTRACTID, &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   rv = nsComposerController::RegisterHTMLEditorCommands(commandTable);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   // we don't know here whether we're being created as an instance,
   // or a service, so we can't become immutable
@@ -199,10 +199,10 @@ nsHTMLEditorDocStateCommandTableConstructor(nsISupports *aOuter, REFNSIID aIID,
   nsresult rv;
   nsCOMPtr<nsIControllerCommandTable> commandTable =
       do_CreateInstance(NS_CONTROLLERCOMMANDTABLE_CONTRACTID, &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   rv = nsComposerController::RegisterEditorDocStateCommands(commandTable);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   // we don't know here whether we're being created as an instance,
   // or a service, so we can't become immutable
diff --git a/editor/composer/src/nsEditingSession.cpp b/editor/composer/src/nsEditingSession.cpp
index 977ed979c41..5fe19c907d3 100644
--- a/editor/composer/src/nsEditingSession.cpp
+++ b/editor/composer/src/nsEditingSession.cpp
@@ -174,15 +174,15 @@ nsEditingSession::MakeWindowEditable(nsIDOMWindow *aWindow,
   // if all this does is setup listeners and I don't need listeners, 
   // can't this step be ignored?? (based on aDoAfterURILoad)
   rv = PrepareForEditing(aWindow);
-  if (NS_FAILED(rv)) return rv;  
+  NS_ENSURE_SUCCESS(rv, rv);  
   
   nsCOMPtr<nsIEditorDocShell> editorDocShell;
   rv = GetEditorDocShellFromWindow(aWindow, getter_AddRefs(editorDocShell));
-  if (NS_FAILED(rv)) return rv;  
+  NS_ENSURE_SUCCESS(rv, rv);  
   
   // set the flag on the docShell to say that it's editable
   rv = editorDocShell->MakeEditable(aDoAfterUriLoad);
-  if (NS_FAILED(rv)) return rv;  
+  NS_ENSURE_SUCCESS(rv, rv);  
 
   // Setup commands common to plaintext and html editors,
   //  including the document creation observers
@@ -191,7 +191,7 @@ nsEditingSession::MakeWindowEditable(nsIDOMWindow *aWindow,
                                     aWindow,
                                     static_cast<nsIEditingSession*>(this),
                                     &mBaseCommandControllerId);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // The second is a controller to monitor doc state,
   // such as creation and "dirty flag"
@@ -199,7 +199,7 @@ nsEditingSession::MakeWindowEditable(nsIDOMWindow *aWindow,
                                     aWindow,
                                     static_cast<nsIEditingSession*>(this),
                                     &mDocStateControllerId);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // aDoAfterUriLoad can be false only when making an existing window editable
   if (!aDoAfterUriLoad)
@@ -274,7 +274,7 @@ nsEditingSession::WindowIsEditable(nsIDOMWindow *aWindow, PRBool *outIsEditable)
   nsCOMPtr<nsIEditorDocShell> editorDocShell;
   nsresult rv = GetEditorDocShellFromWindow(aWindow,
                                             getter_AddRefs(editorDocShell));
-  if (NS_FAILED(rv)) return rv;  
+  NS_ENSURE_SUCCESS(rv, rv);  
 
   return editorDocShell->GetEditable(outIsEditable);
 }
@@ -418,7 +418,7 @@ nsEditingSession::SetupEditorOnWindow(nsIDOMWindow *aWindow)
   // This allows notification of error state
   //  even if we don't create an editor
   rv = mStateMaintainer->Init(aWindow);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   if (mEditorStatus != eEditorCreationInProgress)
   {
@@ -437,19 +437,19 @@ nsEditingSession::SetupEditorOnWindow(nsIDOMWindow *aWindow)
     if (!utils) return NS_ERROR_FAILURE;
 
     rv = utils->GetImageAnimationMode(&mImageAnimationMode);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
     utils->SetImageAnimationMode(imgIContainer::kDontAnimMode);
   }
 
   // create and set editor
   nsCOMPtr<nsIEditorDocShell> editorDocShell = do_QueryInterface(docShell, &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsIEditor> editor = do_CreateInstance(classString, &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   // set the editor on the docShell. The docShell now owns it.
   rv = editorDocShell->SetEditor(editor);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // setup the HTML editor command controller
   if (needHTMLController)
@@ -458,38 +458,38 @@ nsEditingSession::SetupEditorOnWindow(nsIDOMWindow *aWindow)
     rv = SetupEditorCommandController("@mozilla.org/editor/htmleditorcontroller;1",
                                       aWindow, editor,
                                       &mHTMLCommandControllerId);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
 
   // Set mimetype on editor
   rv = editor->SetContentsMIMEType(mimeCType.get());
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsIContentViewer> contentViewer;
   rv = docShell->GetContentViewer(getter_AddRefs(contentViewer));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!contentViewer) return NS_ERROR_FAILURE;
 
   nsCOMPtr<nsIDOMDocument> domDoc;  
   rv = contentViewer->GetDOMDocument(getter_AddRefs(domDoc));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!domDoc) return NS_ERROR_FAILURE;
 
   // Set up as a doc state listener
   // Important! We must have this to broadcast the "obs_documentCreated" message
   rv = editor->AddDocumentStateListener(mStateMaintainer);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // XXXbz we really shouldn't need a presShell here!
   nsCOMPtr<nsIPresShell> presShell;
   rv = docShell->GetPresShell(getter_AddRefs(presShell));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!presShell) return NS_ERROR_FAILURE;
 
   nsCOMPtr<nsISelectionController> selCon = do_QueryInterface(presShell);
   rv = editor->Init(domDoc, presShell, nsnull /* root content */,
                     selCon, mEditorFlags);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsISelection> selection;
   editor->GetSelection(getter_AddRefs(selection));
@@ -497,7 +497,7 @@ nsEditingSession::SetupEditorOnWindow(nsIDOMWindow *aWindow)
   if (!selPriv) return NS_ERROR_FAILURE;
 
   rv = selPriv->AddSelectionListener(mStateMaintainer);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // and as a transaction listener
   nsCOMPtr<nsITransactionManager> txnMgr;
@@ -507,7 +507,7 @@ nsEditingSession::SetupEditorOnWindow(nsIDOMWindow *aWindow)
 
   // Set context on all controllers to be the editor
   rv = SetEditorOnControllers(aWindow, editor);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // Everything went fine!
   mEditorStatus = eEditorOK;
@@ -632,7 +632,7 @@ nsEditingSession::GetEditorForWindow(nsIDOMWindow *aWindow,
   nsCOMPtr<nsIEditorDocShell> editorDocShell;
   nsresult rv = GetEditorDocShellFromWindow(aWindow,
                                             getter_AddRefs(editorDocShell));
-  if (NS_FAILED(rv)) return rv;  
+  NS_ENSURE_SUCCESS(rv, rv);  
   
   return editorDocShell->GetEditor(outEditor);
 }
@@ -837,11 +837,11 @@ nsEditingSession::OnLocationChange(nsIWebProgress *aWebProgress,
 {
   nsCOMPtr<nsIDOMWindow> domWindow;
   nsresult rv = aWebProgress->GetDOMWindow(getter_AddRefs(domWindow));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsIDOMDocument> domDoc;
   rv = domWindow->GetDocument(getter_AddRefs(domDoc));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsIDocument> doc = do_QueryInterface(domDoc);
   if (!doc) return NS_ERROR_FAILURE;
@@ -1054,7 +1054,7 @@ nsEditingSession::EndDocumentLoad(nsIWebProgress *aWebProgress,
           }
   
           mLoadBlankDocTimer = do_CreateInstance("@mozilla.org/timer;1", &rv);
-          if (NS_FAILED(rv)) return rv;
+          NS_ENSURE_SUCCESS(rv, rv);
 
           mEditorStatus = eEditorCreationInProgress;
           mDocShell = do_GetWeakReference(docShell);
@@ -1241,11 +1241,11 @@ nsEditingSession::SetupEditorCommandController(
   nsresult rv;
   nsCOMPtr<nsIDOMWindowInternal> domWindowInt =
                                     do_QueryInterface(aWindow, &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   nsCOMPtr<nsIControllers> controllers;      
   rv = domWindowInt->GetControllers(getter_AddRefs(controllers));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // We only have to create each singleton controller once
   // We know this has happened once we have a controllerId value
@@ -1254,17 +1254,17 @@ nsEditingSession::SetupEditorCommandController(
     nsresult rv;
     nsCOMPtr<nsIController> controller;
     controller = do_CreateInstance(aControllerClassName, &rv);
-    if (NS_FAILED(rv)) return rv;  
+    NS_ENSURE_SUCCESS(rv, rv);  
 
     // We must insert at head of the list to be sure our
     //   controller is found before other implementations
     //   (e.g., not-implemented versions by browser)
     rv = controllers->InsertControllerAt(0, controller);
-    if (NS_FAILED(rv)) return rv;  
+    NS_ENSURE_SUCCESS(rv, rv);  
 
     // Remember the ID for the controller
     rv = controllers->GetControllerId(controller, aControllerId);
-    if (NS_FAILED(rv)) return rv;  
+    NS_ENSURE_SUCCESS(rv, rv);  
   }  
 
   // Set the context
@@ -1286,25 +1286,25 @@ nsEditingSession::SetEditorOnControllers(nsIDOMWindow *aWindow,
   // set the editor on the controller
   nsCOMPtr<nsIDOMWindowInternal> domWindowInt =
                                      do_QueryInterface(aWindow, &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   nsCOMPtr<nsIControllers> controllers;      
   rv = domWindowInt->GetControllers(getter_AddRefs(controllers));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsISupports> editorAsISupports = do_QueryInterface(aEditor);
   if (mBaseCommandControllerId)
   {
     rv = SetContextOnControllerById(controllers, editorAsISupports,
                                     mBaseCommandControllerId);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
 
   if (mDocStateControllerId)
   {
     rv = SetContextOnControllerById(controllers, editorAsISupports,
                                     mDocStateControllerId);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
 
   if (mHTMLCommandControllerId)
diff --git a/editor/libeditor/base/ChangeCSSInlineStyleTxn.cpp b/editor/libeditor/base/ChangeCSSInlineStyleTxn.cpp
index 91ae1c9a532..3807d0ac039 100644
--- a/editor/libeditor/base/ChangeCSSInlineStyleTxn.cpp
+++ b/editor/libeditor/base/ChangeCSSInlineStyleTxn.cpp
@@ -180,7 +180,7 @@ NS_IMETHODIMP ChangeCSSInlineStyleTxn::DoTransaction(void)
 
   nsCOMPtr<nsIDOMCSSStyleDeclaration> cssDecl;
   nsresult result = inlineStyles->GetStyle(getter_AddRefs(cssDecl));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!cssDecl) return NS_ERROR_NULL_POINTER;
 
   nsAutoString propertyNameString;
@@ -188,11 +188,11 @@ NS_IMETHODIMP ChangeCSSInlineStyleTxn::DoTransaction(void)
 
   NS_NAMED_LITERAL_STRING(styleAttr, "style");
   result = mElement->HasAttribute(styleAttr, &mUndoAttributeWasSet);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   nsAutoString values;
   result = cssDecl->GetPropertyValue(propertyNameString, values);
-  if (NS_FAILED(result)) return result;     
+  NS_ENSURE_SUCCESS(result, result);     
   mUndoValue.Assign(values);
 
   // does this property accept more than 1 value ?
@@ -211,26 +211,26 @@ NS_IMETHODIMP ChangeCSSInlineStyleTxn::DoTransaction(void)
       RemoveValueFromListOfValues(values, mValue);
       if (values.IsEmpty()) {
         result = cssDecl->RemoveProperty(propertyNameString, returnString);
-        if (NS_FAILED(result)) return result;     
+        NS_ENSURE_SUCCESS(result, result);     
       }
       else {
         nsAutoString priority;
         result = cssDecl->GetPropertyPriority(propertyNameString, priority);
-        if (NS_FAILED(result)) return result;     
+        NS_ENSURE_SUCCESS(result, result);     
         result = cssDecl->SetProperty(propertyNameString, values,
                                       priority);
-        if (NS_FAILED(result)) return result;     
+        NS_ENSURE_SUCCESS(result, result);     
       }
     }
     else {
       result = cssDecl->RemoveProperty(propertyNameString, returnString);
-      if (NS_FAILED(result)) return result;     
+      NS_ENSURE_SUCCESS(result, result);     
     }
   }
   else {
     nsAutoString priority;
     result = cssDecl->GetPropertyPriority(propertyNameString, priority);
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (multiple) {
       // the property can have more than one value, let's add
       // the value we have to add to the others
@@ -243,16 +243,16 @@ NS_IMETHODIMP ChangeCSSInlineStyleTxn::DoTransaction(void)
       values.Assign(mValue);
     result = cssDecl->SetProperty(propertyNameString, values,
                                   priority);
-    if (NS_FAILED(result)) return result;     
+    NS_ENSURE_SUCCESS(result, result);     
   }
 
   // let's be sure we don't keep an empty style attribute
   PRUint32 length;
   result = cssDecl->GetLength(&length);
-  if (NS_FAILED(result)) return result;     
+  NS_ENSURE_SUCCESS(result, result);     
   if (!length) {
     result = mElement->RemoveAttribute(styleAttr);
-    if (NS_FAILED(result)) return result;     
+    NS_ENSURE_SUCCESS(result, result);     
   }
   else
     mRedoAttributeWasSet = PR_TRUE;
@@ -276,7 +276,7 @@ nsresult ChangeCSSInlineStyleTxn::SetStyle(PRBool aAttributeWasSet,
     if (!inlineStyles) return NS_ERROR_NULL_POINTER;
     nsCOMPtr<nsIDOMCSSStyleDeclaration> cssDecl;
     result = inlineStyles->GetStyle(getter_AddRefs(cssDecl));
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (!cssDecl) return NS_ERROR_NULL_POINTER;
 
     if (aValue.IsEmpty()) {
@@ -288,7 +288,7 @@ nsresult ChangeCSSInlineStyleTxn::SetStyle(PRBool aAttributeWasSet,
       // let's recreate the declaration as it was
       nsAutoString priority;
       result = cssDecl->GetPropertyPriority(propertyNameString, priority);
-      if (NS_FAILED(result)) return result;
+      NS_ENSURE_SUCCESS(result, result);
       result = cssDecl->SetProperty(propertyNameString, aValue, priority);
     }
   }
diff --git a/editor/libeditor/base/CreateElementTxn.cpp b/editor/libeditor/base/CreateElementTxn.cpp
index 0a4cb3e4068..5253d19f53b 100644
--- a/editor/libeditor/base/CreateElementTxn.cpp
+++ b/editor/libeditor/base/CreateElementTxn.cpp
@@ -115,7 +115,7 @@ NS_IMETHODIMP CreateElementTxn::DoTransaction(void)
  
   //new call to use instead to get proper HTML element, bug# 39919
   nsresult result = mEditor->CreateHTMLContent(mTag, getter_AddRefs(newContent));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   nsCOMPtr<nsIDOMElement>newElement = do_QueryInterface(newContent);
   if (!newElement) return NS_ERROR_NULL_POINTER;
   mNewNode = do_QueryInterface(newElement);
@@ -149,10 +149,10 @@ NS_IMETHODIMP CreateElementTxn::DoTransaction(void)
       if (mOffsetInParent>count)
         mOffsetInParent = count;
       result = childNodes->Item(mOffsetInParent, getter_AddRefs(mRefNode));
-      if (NS_FAILED(result)) return result; // note, it's ok for mRefNode to be null.  that means append
+      NS_ENSURE_SUCCESS(result, result); // note, it's ok for mRefNode to be null.  that means append
 
       result = mParent->InsertBefore(mNewNode, mRefNode, getter_AddRefs(resultNode));
-      if (NS_FAILED(result)) return result; 
+      NS_ENSURE_SUCCESS(result, result); 
 
       // only set selection to insertion point if editor gives permission
       PRBool bAdjustSelection;
@@ -161,12 +161,12 @@ NS_IMETHODIMP CreateElementTxn::DoTransaction(void)
       {
         nsCOMPtr<nsISelection> selection;
         result = mEditor->GetSelection(getter_AddRefs(selection));
-        if (NS_FAILED(result)) return result;
+        NS_ENSURE_SUCCESS(result, result);
         if (!selection) return NS_ERROR_NULL_POINTER;
 
         PRInt32 offset=0;
         result = nsEditor::GetChildOffset(mNewNode, mParent, offset);
-        if (NS_FAILED(result)) return result;
+        NS_ENSURE_SUCCESS(result, result);
 
         result = selection->Collapse(mParent, offset+1);
         NS_ASSERTION((NS_SUCCEEDED(result)), "selection could not be collapsed after insert.");
diff --git a/editor/libeditor/base/DeleteRangeTxn.cpp b/editor/libeditor/base/DeleteRangeTxn.cpp
index 81a55c16f5a..2d0056b0799 100644
--- a/editor/libeditor/base/DeleteRangeTxn.cpp
+++ b/editor/libeditor/base/DeleteRangeTxn.cpp
@@ -196,7 +196,7 @@ NS_IMETHODIMP DeleteRangeTxn::DoTransaction(void)
     result = EditAggregateTxn::DoTransaction();
   }
 
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   
   // only set selection to deletion point if editor gives permission
   PRBool bAdjustSelection;
@@ -205,7 +205,7 @@ NS_IMETHODIMP DeleteRangeTxn::DoTransaction(void)
   {
     nsCOMPtr<nsISelection> selection;
     result = mEditor->GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (!selection) return NS_ERROR_NULL_POINTER;
     result = selection->Collapse(mStartParent, mStartOffset);
   }
@@ -274,7 +274,7 @@ DeleteRangeTxn::CreateTxnsToDeleteBetween(nsIDOMNode *aStartParent,
   {
     nsCOMPtr<nsIDOMNodeList> children;
     result = aStartParent->GetChildNodes(getter_AddRefs(children));
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (!children) return NS_ERROR_NULL_POINTER;
 
 #ifdef DEBUG
@@ -287,7 +287,7 @@ DeleteRangeTxn::CreateTxnsToDeleteBetween(nsIDOMNode *aStartParent,
     {
       nsCOMPtr<nsIDOMNode> child;
       result = children->Item(i, getter_AddRefs(child));
-      if (NS_FAILED(result)) return result;
+      NS_ENSURE_SUCCESS(result, result);
       if (!child) return NS_ERROR_NULL_POINTER;
 
       nsRefPtr<DeleteElementTxn> txn = new DeleteElementTxn();
@@ -345,7 +345,7 @@ NS_IMETHODIMP DeleteRangeTxn::CreateTxnsToDeleteNodesBetween()
   if (!iter) return NS_ERROR_NULL_POINTER;
 
   nsresult result = iter->Init(mRange);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   while (!iter->IsDone() && NS_SUCCEEDED(result))
   {
diff --git a/editor/libeditor/base/DeleteTextTxn.cpp b/editor/libeditor/base/DeleteTextTxn.cpp
index 13bcf17b223..69e3e8acaa3 100644
--- a/editor/libeditor/base/DeleteTextTxn.cpp
+++ b/editor/libeditor/base/DeleteTextTxn.cpp
@@ -107,7 +107,7 @@ NS_IMETHODIMP DeleteTextTxn::DoTransaction(void)
   nsresult result = mElement->SubstringData(mOffset, mNumCharsToDelete, mDeletedText);
   NS_ASSERTION(NS_SUCCEEDED(result), "could not get text to delete.");
   result = mElement->DeleteData(mOffset, mNumCharsToDelete);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   if (mRangeUpdater) 
     mRangeUpdater->SelAdjDeleteText(mElement, mOffset, mNumCharsToDelete);
@@ -119,7 +119,7 @@ NS_IMETHODIMP DeleteTextTxn::DoTransaction(void)
   {
     nsCOMPtr<nsISelection> selection;
     result = mEditor->GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (!selection) return NS_ERROR_NULL_POINTER;
     result = selection->Collapse(mElement, mOffset);
     NS_ASSERTION((NS_SUCCEEDED(result)), "selection could not be collapsed after undo of deletetext.");
diff --git a/editor/libeditor/base/InsertElementTxn.cpp b/editor/libeditor/base/InsertElementTxn.cpp
index c333a1ea90e..860303b8225 100644
--- a/editor/libeditor/base/InsertElementTxn.cpp
+++ b/editor/libeditor/base/InsertElementTxn.cpp
@@ -109,7 +109,7 @@ NS_IMETHODIMP InsertElementTxn::DoTransaction(void)
 
   nsCOMPtr<nsIDOMNodeList> childNodes;
   nsresult result = mParent->GetChildNodes(getter_AddRefs(childNodes));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   nsCOMPtr<nsIDOMNode>refNode;
   if (childNodes)
   {
@@ -119,7 +119,7 @@ NS_IMETHODIMP InsertElementTxn::DoTransaction(void)
     // -1 is sentinel value meaning "append at end"
     if (mOffset == -1) mOffset = count;
     result = childNodes->Item(mOffset, getter_AddRefs(refNode));
-    if (NS_FAILED(result)) return result; 
+    NS_ENSURE_SUCCESS(result, result); 
     // note, it's ok for mRefNode to be null.  that means append
   }
 
@@ -127,7 +127,7 @@ NS_IMETHODIMP InsertElementTxn::DoTransaction(void)
 
   nsCOMPtr<nsIDOMNode> resultNode;
   result = mParent->InsertBefore(mNode, refNode, getter_AddRefs(resultNode));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!resultNode) return NS_ERROR_NULL_POINTER;
 
   // only set selection to insertion point if editor gives permission
@@ -137,7 +137,7 @@ NS_IMETHODIMP InsertElementTxn::DoTransaction(void)
   {
     nsCOMPtr<nsISelection> selection;
     result = mEditor->GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (!selection) return NS_ERROR_NULL_POINTER;
     // place the selection just after the inserted element
     selection->Collapse(mParent, mOffset+1);
diff --git a/editor/libeditor/base/InsertTextTxn.cpp b/editor/libeditor/base/InsertTextTxn.cpp
index e2e55212ae3..ce3bc50b821 100644
--- a/editor/libeditor/base/InsertTextTxn.cpp
+++ b/editor/libeditor/base/InsertTextTxn.cpp
@@ -104,7 +104,7 @@ NS_IMETHODIMP InsertTextTxn::DoTransaction(void)
   if (!mElement || !mEditor) { return NS_ERROR_NOT_INITIALIZED; }
 
   nsresult result = mElement->InsertData(mOffset, mStringToInsert);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   // only set selection to insertion point if editor gives permission
   PRBool bAdjustSelection;
@@ -113,7 +113,7 @@ NS_IMETHODIMP InsertTextTxn::DoTransaction(void)
   {
     nsCOMPtr<nsISelection> selection;
     result = mEditor->GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (!selection) return NS_ERROR_NULL_POINTER;
     result = selection->Collapse(mElement, mOffset+mStringToInsert.Length());
     NS_ASSERTION((NS_SUCCEEDED(result)), "selection could not be collapsed after insert.");
diff --git a/editor/libeditor/base/JoinElementTxn.cpp b/editor/libeditor/base/JoinElementTxn.cpp
index 97eb41327cc..02f625c666f 100644
--- a/editor/libeditor/base/JoinElementTxn.cpp
+++ b/editor/libeditor/base/JoinElementTxn.cpp
@@ -76,7 +76,7 @@ NS_IMETHODIMP JoinElementTxn::Init(nsEditor   *aEditor,
   mLeftNode = do_QueryInterface(aLeftNode);
   nsCOMPtr<nsIDOMNode>leftParent;
   nsresult result = mLeftNode->GetParentNode(getter_AddRefs(leftParent));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!mEditor->IsModifiableNode(leftParent)) {
     return NS_ERROR_FAILURE;
   }
@@ -104,13 +104,13 @@ NS_IMETHODIMP JoinElementTxn::DoTransaction(void)
   // get the parent node
   nsCOMPtr<nsIDOMNode>leftParent;
   nsresult result = mLeftNode->GetParentNode(getter_AddRefs(leftParent));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!leftParent) return NS_ERROR_NULL_POINTER;
 
   // verify that mLeftNode and mRightNode have the same parent
   nsCOMPtr<nsIDOMNode>rightParent;
   result = mRightNode->GetParentNode(getter_AddRefs(rightParent));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!rightParent) return NS_ERROR_NULL_POINTER;
 
   if (leftParent==rightParent)
@@ -126,7 +126,7 @@ NS_IMETHODIMP JoinElementTxn::DoTransaction(void)
     {
       nsCOMPtr<nsIDOMNodeList> childNodes;
       result = mLeftNode->GetChildNodes(getter_AddRefs(childNodes));
-      if (NS_FAILED(result)) return result;
+      NS_ENSURE_SUCCESS(result, result);
       if (childNodes) 
       {
         childNodes->GetLength(&mOffset);
diff --git a/editor/libeditor/base/PlaceholderTxn.cpp b/editor/libeditor/base/PlaceholderTxn.cpp
index 6a0d9cc692b..c691be40db0 100644
--- a/editor/libeditor/base/PlaceholderTxn.cpp
+++ b/editor/libeditor/base/PlaceholderTxn.cpp
@@ -93,14 +93,14 @@ NS_IMETHODIMP PlaceholderTxn::UndoTransaction(void)
 {
   // undo txns
   nsresult res = EditAggregateTxn::UndoTransaction();
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   if (!mStartSel) return NS_ERROR_NULL_POINTER;
 
   // now restore selection
   nsCOMPtr<nsISelection> selection;
   res = mEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   return mStartSel->RestoreSelection(selection);
 }
@@ -110,12 +110,12 @@ NS_IMETHODIMP PlaceholderTxn::RedoTransaction(void)
 {
   // redo txns
   nsresult res = EditAggregateTxn::RedoTransaction();
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // now restore selection
   nsCOMPtr<nsISelection> selection;
   res = mEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   return mEndSel.RestoreSelection(selection);
 }
@@ -290,7 +290,7 @@ NS_IMETHODIMP PlaceholderTxn::RememberEndingSelection()
 {
   nsCOMPtr<nsISelection> selection;
   nsresult res = mEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   return mEndSel.SaveSelection(selection);
 }
diff --git a/editor/libeditor/base/SetDocTitleTxn.cpp b/editor/libeditor/base/SetDocTitleTxn.cpp
index 97bb08cdbb9..c49b2cf1e66 100644
--- a/editor/libeditor/base/SetDocTitleTxn.cpp
+++ b/editor/libeditor/base/SetDocTitleTxn.cpp
@@ -91,7 +91,7 @@ nsresult SetDocTitleTxn::SetDomTitle(const nsAString& aTitle)
 
   nsCOMPtr<nsIDOMNodeList> titleList;
   res = domDoc->GetElementsByTagName(NS_LITERAL_STRING("title"), getter_AddRefs(titleList));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // First assume we will NOT really do anything
   // (transaction will not be pushed on stack)
@@ -101,7 +101,7 @@ nsresult SetDocTitleTxn::SetDomTitle(const nsAString& aTitle)
   if(titleList)
   {
     res = titleList->Item(0, getter_AddRefs(titleNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (titleNode)
     {
       // Delete existing child textnode of title node
@@ -134,7 +134,7 @@ nsresult SetDocTitleTxn::SetDomTitle(const nsAString& aTitle)
   // Get the <HEAD> node, create a <TITLE> and insert it under the HEAD
   nsCOMPtr<nsIDOMNodeList> headList;
   res = domDoc->GetElementsByTagName(NS_LITERAL_STRING("head"),getter_AddRefs(headList));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!headList) return NS_ERROR_FAILURE;
   
   nsCOMPtr<nsIDOMNode>headNode;
@@ -149,7 +149,7 @@ nsresult SetDocTitleTxn::SetDomTitle(const nsAString& aTitle)
     // Didn't find one above: Create a new one
     nsCOMPtr<nsIDOMElement>titleElement;
     res = domDoc->CreateElement(NS_LITERAL_STRING("title"), getter_AddRefs(titleElement));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!titleElement) return NS_ERROR_FAILURE;
 
     titleNode = do_QueryInterface(titleElement);
@@ -159,7 +159,7 @@ nsresult SetDocTitleTxn::SetDomTitle(const nsAString& aTitle)
     // after all existing HEAD children
     nsCOMPtr<nsIDOMNodeList> children;
     res = headNode->GetChildNodes(getter_AddRefs(children));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (children)
       children->GetLength(&newTitleIndex);
   }
@@ -170,7 +170,7 @@ nsresult SetDocTitleTxn::SetDomTitle(const nsAString& aTitle)
   {
     nsCOMPtr<nsIDOMText> textNode;
     res = domDoc->CreateTextNode(aTitle, getter_AddRefs(textNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     nsCOMPtr<nsIDOMNode> newNode = do_QueryInterface(textNode);
     if (!newNode) return NS_ERROR_FAILURE;
 
@@ -185,7 +185,7 @@ nsresult SetDocTitleTxn::SetDomTitle(const nsAString& aTitle)
       // This is an undoable transaction
       res = editor->InsertNode(newNode, titleNode, 0);
     }
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   if (newTitleNode)
diff --git a/editor/libeditor/base/SplitElementTxn.cpp b/editor/libeditor/base/SplitElementTxn.cpp
index 27c14dd8b4d..8e1a3973fcd 100644
--- a/editor/libeditor/base/SplitElementTxn.cpp
+++ b/editor/libeditor/base/SplitElementTxn.cpp
@@ -98,7 +98,7 @@ NS_IMETHODIMP SplitElementTxn::DoTransaction(void)
   // create a new node
   nsresult result = mExistingRightNode->CloneNode(PR_FALSE, getter_AddRefs(mNewLeftNode));
   NS_ASSERTION(((NS_SUCCEEDED(result)) && (mNewLeftNode)), "could not create element.");
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!mNewLeftNode) return NS_ERROR_NULL_POINTER;
   mEditor->MarkNodeDirty(mExistingRightNode);
 
@@ -112,7 +112,7 @@ NS_IMETHODIMP SplitElementTxn::DoTransaction(void)
 
   // get the parent node
   result = mExistingRightNode->GetParentNode(getter_AddRefs(mParent));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!mParent) return NS_ERROR_NULL_POINTER;
 
   // insert the new node
@@ -121,7 +121,7 @@ NS_IMETHODIMP SplitElementTxn::DoTransaction(void)
   {
     nsCOMPtr<nsISelection>selection;
     mEditor->GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (!selection) return NS_ERROR_NULL_POINTER;
     result = selection->Collapse(mNewLeftNode, mOffset);
   }
diff --git a/editor/libeditor/base/nsEditor.cpp b/editor/libeditor/base/nsEditor.cpp
index 6ef9cd72e5d..ed761b03d5d 100644
--- a/editor/libeditor/base/nsEditor.cpp
+++ b/editor/libeditor/base/nsEditor.cpp
@@ -596,7 +596,7 @@ nsEditor::DoTransaction(nsITransaction *aTxn)
     {
       nsCOMPtr<nsITransaction> topTxn;
       result = mTxnMgr->PeekUndoStack(getter_AddRefs(topTxn));
-      if (NS_FAILED(result)) return result;
+      NS_ENSURE_SUCCESS(result, result);
       if (topTxn)
       {
         plcTxn = do_QueryInterface(topTxn);
@@ -868,7 +868,7 @@ nsEditor::BeginPlaceHolderTransaction(nsIAtom *aName)
     mPlaceHolderName = aName;
     nsCOMPtr<nsISelection> selection;
     nsresult res = GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     mSelState = new nsSelectionState();
     if (!mSelState)
       return NS_ERROR_OUT_OF_MEMORY;
@@ -1028,7 +1028,7 @@ NS_IMETHODIMP nsEditor::BeginningOfDocument()
       if (!parentNode) { return NS_ERROR_NULL_POINTER; }
       PRInt32 offsetInParent;
       result = nsEditor::GetChildOffset(firstNode, parentNode, offsetInParent);
-      if (NS_FAILED(result)) return result;
+      NS_ENSURE_SUCCESS(result, result);
       result = selection->Collapse(parentNode, offsetInParent);
     }
   }
@@ -1049,7 +1049,7 @@ nsEditor::EndOfDocument()
   // get selection 
   nsCOMPtr<nsISelection> selection; 
   res = GetSelection(getter_AddRefs(selection)); 
-  if (NS_FAILED(res)) return res; 
+  NS_ENSURE_SUCCESS(res, res); 
   if (!selection)   return NS_ERROR_NULL_POINTER; 
   
   // get the root element 
@@ -1060,7 +1060,7 @@ nsEditor::EndOfDocument()
   // get the length of the rot element 
   PRUint32 len; 
   res = GetLengthOfDOMNode(rootElement, len); 
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // set the selection to after the last child of the root element 
   return selection->Collapse(rootElement, (PRInt32)len); 
@@ -1409,11 +1409,11 @@ nsEditor::JoinNodes(nsIDOMNode * aLeftNode,
   // remember some values; later used for saved selection updating.
   // find the offset between the nodes to be joined.
   nsresult result = GetChildOffset(aRightNode, aParent, offset);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   // find the number of children of the lefthand node
   PRUint32 oldLeftNodeLen;
   result = GetLengthOfDOMNode(aLeftNode, oldLeftNodeLen);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   for (i = 0; i < mActionListeners.Count(); i++)
     mActionListeners[i]->WillJoinNodes(aLeftNode, aRightNode, aParent);
@@ -1441,7 +1441,7 @@ NS_IMETHODIMP nsEditor::DeleteNode(nsIDOMNode * aElement)
 
   // save node location for selection updating code.
   nsresult result = GetNodeLocation(aElement, address_of(parent), &offset);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   for (i = 0; i < mActionListeners.Count(); i++)
     mActionListeners[i]->WillDeleteNode(aElement);
@@ -1476,7 +1476,7 @@ nsEditor::ReplaceContainer(nsIDOMNode *inNode,
   nsCOMPtr<nsIDOMNode> parent;
   PRInt32 offset;
   nsresult res = GetNodeLocation(inNode, address_of(parent), &offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // create new container
   nsCOMPtr<nsIContent> newContent;
@@ -1484,20 +1484,20 @@ nsEditor::ReplaceContainer(nsIDOMNode *inNode,
   //new call to use instead to get proper HTML element, bug# 39919
   res = CreateHTMLContent(aNodeType, getter_AddRefs(newContent));
   nsCOMPtr<nsIDOMElement> elem = do_QueryInterface(newContent);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
     *outNode = do_QueryInterface(elem);
   
   // set attribute if needed
   if (aAttribute && aValue && !aAttribute->IsEmpty())
   {
     res = elem->SetAttribute(*aAttribute, *aValue);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   if (aCloneAttributes)
   {
     nsCOMPtr<nsIDOMNode>newNode = do_QueryInterface(elem);
     res = CloneAttributes(newNode, inNode);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   // notify our internal selection state listener
@@ -1513,16 +1513,16 @@ nsEditor::ReplaceContainer(nsIDOMNode *inNode,
     {
       inNode->GetFirstChild(getter_AddRefs(child));
       res = DeleteNode(child);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       res = InsertNode(child, *outNode, -1);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       inNode->HasChildNodes(&bHasMoreChildren);
     }
   }
   // insert new container into tree
   res = InsertNode( *outNode, parent, offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // delete old container
   return DeleteNode(inNode);
@@ -1541,7 +1541,7 @@ nsEditor::RemoveContainer(nsIDOMNode *inNode)
   PRInt32 offset;
   
   nsresult res = GetNodeLocation(inNode, address_of(parent), &offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // loop through the child nodes of inNode and promote them
   // into inNode's parent.
@@ -1549,7 +1549,7 @@ nsEditor::RemoveContainer(nsIDOMNode *inNode)
   inNode->HasChildNodes(&bHasMoreChildren);
   nsCOMPtr<nsIDOMNodeList> nodeList;
   res = inNode->GetChildNodes(getter_AddRefs(nodeList));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!nodeList) return NS_ERROR_NULL_POINTER;
   PRUint32 nodeOrigLen;
   nodeList->GetLength(&nodeOrigLen);
@@ -1562,9 +1562,9 @@ nsEditor::RemoveContainer(nsIDOMNode *inNode)
   {
     inNode->GetLastChild(getter_AddRefs(child));
     res = DeleteNode(child);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = InsertNode(child, parent, offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     inNode->HasChildNodes(&bHasMoreChildren);
   }
   return DeleteNode(inNode);
@@ -1589,7 +1589,7 @@ nsEditor::InsertContainerAbove( nsIDOMNode *inNode,
   nsCOMPtr<nsIDOMNode> parent;
   PRInt32 offset;
   nsresult res = GetNodeLocation(inNode, address_of(parent), &offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // create new container
   nsCOMPtr<nsIContent> newContent;
@@ -1597,14 +1597,14 @@ nsEditor::InsertContainerAbove( nsIDOMNode *inNode,
   //new call to use instead to get proper HTML element, bug# 39919
   res = CreateHTMLContent(aNodeType, getter_AddRefs(newContent));
   nsCOMPtr<nsIDOMElement> elem = do_QueryInterface(newContent);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   *outNode = do_QueryInterface(elem);
   
   // set attribute if needed
   if (aAttribute && aValue && !aAttribute->IsEmpty())
   {
     res = elem->SetAttribute(*aAttribute, *aValue);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   // notify our internal selection state listener
@@ -1612,12 +1612,12 @@ nsEditor::InsertContainerAbove( nsIDOMNode *inNode,
   
   // put inNode in new parent, outNode
   res = DeleteNode(inNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   {
     nsAutoTxnsConserveSelection conserveSelection(this);
     res = InsertNode(inNode, *outNode, 0);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   // put new parent in doc
@@ -1641,7 +1641,7 @@ nsEditor::MoveNode(nsIDOMNode *aNode, nsIDOMNode *aParent, PRInt32 aOffset)
     PRUint32 unsignedOffset;
     // magic value meaning "move to end of aParent"
     res = GetLengthOfDOMNode(aParent, unsignedOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     aOffset = (PRInt32)unsignedOffset;
   }
   
@@ -1659,7 +1659,7 @@ nsEditor::MoveNode(nsIDOMNode *aNode, nsIDOMNode *aParent, PRInt32 aOffset)
 
   // put aNode in new parent
   res = DeleteNode(aNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   return InsertNode(aNode, aParent, aOffset);
 }
 
@@ -2311,16 +2311,16 @@ NS_IMETHODIMP nsEditor::InsertTextImpl(const nsAString& aStringToInsert,
     {
       // create a text node
       res = aDoc->CreateTextNode(EmptyString(), getter_AddRefs(nodeAsText));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!nodeAsText) return NS_ERROR_NULL_POINTER;
       nsCOMPtr<nsIDOMNode> newNode = do_QueryInterface(nodeAsText);
       // then we insert it into the dom tree
       res = InsertNode(newNode, *aInOutNode, offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       offset = 0;
     }
     res = InsertTextIntoTextNodeImpl(aStringToInsert, nodeAsText, offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   else
   {
@@ -2328,7 +2328,7 @@ NS_IMETHODIMP nsEditor::InsertTextImpl(const nsAString& aStringToInsert,
     {
       // we are inserting text into an existing text node.
       res = InsertTextIntoTextNodeImpl(aStringToInsert, nodeAsText, offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       *aInOutOffset += aStringToInsert.Length();
     }
     else
@@ -2336,12 +2336,12 @@ NS_IMETHODIMP nsEditor::InsertTextImpl(const nsAString& aStringToInsert,
       // we are inserting text into a non-text node
       // first we have to create a textnode (this also populates it with the text)
       res = aDoc->CreateTextNode(aStringToInsert, getter_AddRefs(nodeAsText));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!nodeAsText) return NS_ERROR_NULL_POINTER;
       nsCOMPtr<nsIDOMNode> newNode = do_QueryInterface(nodeAsText);
       // then we insert it into the dom tree
       res = InsertNode(newNode, *aInOutNode, offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       *aInOutNode = newNode;
       *aInOutOffset = aStringToInsert.Length();
     }
@@ -2417,7 +2417,7 @@ nsresult nsEditor::InsertTextIntoTextNodeImpl(const nsAString& aStringToInsert,
                                     getter_AddRefs(insertTxn));
     txn = insertTxn;
   }
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   // let listeners know what's up
   PRInt32 i;
@@ -2551,7 +2551,7 @@ nsEditor::NotifyDocumentListeners(TDocumentListenerNotification aNotificationTyp
       {
         PRBool docIsDirty;
         rv = GetDocumentModified(&docIsDirty);
-        if (NS_FAILED(rv)) return rv;
+        NS_ENSURE_SUCCESS(rv, rv);
         
         if (docIsDirty == mDocDirtyState)
           return NS_OK;
@@ -2697,7 +2697,7 @@ nsEditor::SplitNodeImpl(nsIDOMNode * aExistingRightNode,
     // get selection
     nsCOMPtr<nsISelection> selection;
     result = GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (!selection) return NS_ERROR_NULL_POINTER;
 
     // remember some selection points
@@ -2838,12 +2838,12 @@ nsEditor::JoinNodesImpl(nsIDOMNode * aNodeToKeep,
 
     PRUint32 firstNodeLength;
     result = GetLengthOfDOMNode(leftNode, firstNodeLength);
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     nsCOMPtr<nsIDOMNode> parent;
     result = GetNodeLocation(aNodeToJoin, address_of(parent), &joinOffset);
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     result = GetNodeLocation(aNodeToKeep, address_of(parent), &keepOffset);
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     
     // if selection endpoint is between the nodes, remember it as being
     // in the one that is going away instead.  This simplifies later selection
@@ -3199,7 +3199,7 @@ nsEditor::GetPriorNode(nsIDOMNode  *aCurrentNode,
 
   nsCOMPtr<nsIDOMNode> candidate;
   result = GetPriorNodeImpl(aCurrentNode, aEditableNode, address_of(candidate), bNoBlockCrossing);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   
   if (!candidate)
   {
@@ -3310,7 +3310,7 @@ nsEditor::GetNextNode(nsIDOMNode  *aCurrentNode,
   nsCOMPtr<nsIDOMNode> candidate;
   nsresult result = GetNextNodeImpl(aCurrentNode, aEditableNode,
                                     address_of(candidate), bNoBlockCrossing);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   
   if (!candidate)
   {
@@ -3960,19 +3960,19 @@ nsEditor::SplitNodeDeep(nsIDOMNode *aNode,
     PRUint32 len;
     PRBool bDoSplit = PR_FALSE;
     res = GetLengthOfDOMNode(nodeToSplit, len);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     if (!(aNoEmptyContainers || nodeAsText) || (offset && (offset != (PRInt32)len)))
     {
       bDoSplit = PR_TRUE;
       res = SplitNode(nodeToSplit, offset, getter_AddRefs(tempNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (outRightNode) *outRightNode = nodeToSplit;
       if (outLeftNode)  *outLeftNode  = tempNode;
     }
 
     res = nodeToSplit->GetParentNode(getter_AddRefs(parentNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!parentNode) return NS_ERROR_FAILURE;
 
     if (!bDoSplit && offset)  // must be "end of text node" case, we didn't split it, just move past it
@@ -4040,7 +4040,7 @@ nsEditor::JoinNodeDeep(nsIDOMNode *aLeftNode,
     else
     {
       res = GetLengthOfDOMNode(leftNodeToJoin, length);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     
     *aOutJoinNode = rightNodeToJoin;
@@ -4048,7 +4048,7 @@ nsEditor::JoinNodeDeep(nsIDOMNode *aLeftNode,
     
     // do the join
     res = JoinNodes(leftNodeToJoin, rightNodeToJoin, parentNode);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     if (IsTextNode(parentNode)) // we've joined all the way down to text nodes, we're done!
       return NS_OK;
@@ -4201,7 +4201,7 @@ nsEditor::DeleteSelectionImpl(nsIEditor::EDirection aAction)
 {
   nsCOMPtr<nsISelection>selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsRefPtr<EditAggregateTxn> txn;
   nsCOMPtr<nsIDOMNode> deleteNode;
   PRInt32 deleteCharOffset = 0, deleteCharLength = 0;
@@ -4265,7 +4265,7 @@ nsEditor::DeleteSelectionAndCreateNode(const nsAString& aTag,
   // we want the selection to be just after the new node
   nsCOMPtr<nsISelection> selection;
   result = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!selection) return NS_ERROR_NULL_POINTER;
   return selection->Collapse(parentSelectedNode, offsetOfNewNode+1);
 }
@@ -4321,7 +4321,7 @@ nsEditor::DeleteSelectionAndPrepareToCreateNode(nsCOMPtr<nsIDOMNode> &parentSele
   nsresult result=NS_ERROR_NOT_INITIALIZED;
   nsCOMPtr<nsISelection> selection;
   result = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   PRBool collapsed;
@@ -4905,21 +4905,21 @@ nsEditor::AppendNodeToSelectionAsRange(nsIDOMNode *aNode)
   if (!aNode) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if(!selection) return NS_ERROR_FAILURE;
 
   nsCOMPtr<nsIDOMNode> parentNode;
   res = aNode->GetParentNode(getter_AddRefs(parentNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!parentNode) return NS_ERROR_NULL_POINTER;
   
   PRInt32 offset;
   res = GetChildOffset(aNode, parentNode, offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   nsCOMPtr<nsIDOMRange> range;
   res = CreateRange(parentNode, offset, parentNode, offset+1, getter_AddRefs(range));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!range) return NS_ERROR_NULL_POINTER;
 
   return selection->AddRange(range);
@@ -4929,7 +4929,7 @@ nsresult nsEditor::ClearSelection()
 {
   nsCOMPtr<nsISelection> selection;
   nsresult res = nsEditor::GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_FAILURE;
   return selection->RemoveAllRanges();  
 }
diff --git a/editor/libeditor/base/nsEditorEventListener.cpp b/editor/libeditor/base/nsEditorEventListener.cpp
index b3cb5752a0a..fc53a6cc0d6 100644
--- a/editor/libeditor/base/nsEditorEventListener.cpp
+++ b/editor/libeditor/base/nsEditorEventListener.cpp
@@ -572,7 +572,7 @@ nsEditorEventListener::DragOver(nsIDOMDragEvent* aDragEvent)
     {
       PRInt32 offset = 0;
       nsresult rv = nsuiEvent->GetRangeOffset(&offset);
-      if (NS_FAILED(rv)) return rv;
+      NS_ENSURE_SUCCESS(rv, rv);
 
       // to avoid flicker, we could track the node and offset to see if we moved
       if (mCaretDrawn)
@@ -721,11 +721,11 @@ nsEditorEventListener::CanDrop(nsIDOMDragEvent* aEvent)
 
   nsCOMPtr<nsIDOMDocument> domdoc;
   nsresult rv = mEditor->GetDocument(getter_AddRefs(domdoc));
-  if (NS_FAILED(rv)) return PR_FALSE;
+  NS_ENSURE_SUCCESS(rv, PR_FALSE);
 
   nsCOMPtr<nsIDOMDocument> sourceDoc;
   rv = sourceNode->GetOwnerDocument(getter_AddRefs(sourceDoc));
-  if (NS_FAILED(rv)) return PR_FALSE;
+  NS_ENSURE_SUCCESS(rv, PR_FALSE);
   if (domdoc == sourceDoc)      // source and dest are the same document; disallow drops within the selection
   {
     nsCOMPtr<nsISelection> selection;
@@ -735,7 +735,7 @@ nsEditorEventListener::CanDrop(nsIDOMDragEvent* aEvent)
     
     PRBool isCollapsed;
     rv = selection->GetIsCollapsed(&isCollapsed);
-    if (NS_FAILED(rv)) return PR_FALSE;
+    NS_ENSURE_SUCCESS(rv, PR_FALSE);
   
     // Don't bother if collapsed - can always drop
     if (!isCollapsed)
@@ -749,11 +749,11 @@ nsEditorEventListener::CanDrop(nsIDOMDragEvent* aEvent)
 
       PRInt32 offset = 0;
       rv = nsuiEvent->GetRangeOffset(&offset);
-      if (NS_FAILED(rv)) return PR_FALSE;
+      NS_ENSURE_SUCCESS(rv, PR_FALSE);
 
       PRInt32 rangeCount;
       rv = selection->GetRangeCount(&rangeCount);
-      if (NS_FAILED(rv)) return PR_FALSE;
+      NS_ENSURE_SUCCESS(rv, PR_FALSE);
 
       for (PRInt32 i = 0; i < rangeCount; i++)
       {
diff --git a/editor/libeditor/base/nsEditorUtils.cpp b/editor/libeditor/base/nsEditorUtils.cpp
index af7182685f8..fc17ed0e735 100644
--- a/editor/libeditor/base/nsEditorUtils.cpp
+++ b/editor/libeditor/base/nsEditorUtils.cpp
@@ -105,7 +105,7 @@ nsDOMIterator::Init(nsIDOMRange* aRange)
 {
   nsresult res;
   mIter = do_CreateInstance("@mozilla.org/content/post-content-iterator;1", &res);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!mIter) return NS_ERROR_FAILURE;
   return mIter->Init(aRange);
 }
@@ -115,7 +115,7 @@ nsDOMIterator::Init(nsIDOMNode* aNode)
 {
   nsresult res;
   mIter = do_CreateInstance("@mozilla.org/content/post-content-iterator;1", &res);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!mIter) return NS_ERROR_FAILURE;
   nsCOMPtr<nsIContent> content = do_QueryInterface(aNode);
   return mIter->Init(content);
@@ -173,7 +173,7 @@ nsDOMSubtreeIterator::Init(nsIDOMRange* aRange)
 {
   nsresult res;
   mIter = do_CreateInstance("@mozilla.org/content/subtree-content-iterator;1", &res);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!mIter) return NS_ERROR_FAILURE;
   return mIter->Init(aRange);
 }
@@ -183,7 +183,7 @@ nsDOMSubtreeIterator::Init(nsIDOMNode* aNode)
 {
   nsresult res;
   mIter = do_CreateInstance("@mozilla.org/content/subtree-content-iterator;1", &res);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!mIter) return NS_ERROR_FAILURE;
   nsCOMPtr<nsIContent> content = do_QueryInterface(aNode);
   return mIter->Init(content);
@@ -205,7 +205,7 @@ nsEditorUtils::IsDescendantOf(nsIDOMNode *aNode, nsIDOMNode *aParent, PRInt32 *a
   do
   {
     res = node->GetParentNode(getter_AddRefs(parent));
-    if (NS_FAILED(res)) return PR_FALSE;
+    NS_ENSURE_SUCCESS(res, PR_FALSE);
     if (parent == aParent) 
     {
       if (aOffset)
diff --git a/editor/libeditor/base/nsSelectionState.cpp b/editor/libeditor/base/nsSelectionState.cpp
index 3f93c0c0703..ed82a2cbfa9 100644
--- a/editor/libeditor/base/nsSelectionState.cpp
+++ b/editor/libeditor/base/nsSelectionState.cpp
@@ -342,11 +342,11 @@ nsRangeUpdater::SelAdjSplitNode(nsIDOMNode *aOldRightNode, PRInt32 aOffset, nsID
   nsCOMPtr<nsIDOMNode> parent;
   PRInt32 offset;
   nsresult result = nsEditor::GetNodeLocation(aOldRightNode, address_of(parent), &offset);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   
   // first part is same as inserting aNewLeftnode
   result = SelAdjInsertNode(parent,offset-1);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   // next step is to check for range enpoints inside aOldRightNode
   nsRangeStore *item;
diff --git a/editor/libeditor/html/TypeInState.cpp b/editor/libeditor/html/TypeInState.cpp
index c6ebe6ff427..516b99aeda3 100644
--- a/editor/libeditor/html/TypeInState.cpp
+++ b/editor/libeditor/html/TypeInState.cpp
@@ -74,7 +74,7 @@ nsresult TypeInState::UpdateSelState(nsISelection *aSelection)
   PRBool isCollapsed = PR_FALSE;
   nsresult result = aSelection->GetIsCollapsed(&isCollapsed);
 
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   if (isCollapsed)
   {
@@ -101,7 +101,7 @@ NS_IMETHODIMP TypeInState::NotifySelectionChanged(nsIDOMDocument *, nsISelection
     PRBool isCollapsed = PR_FALSE;
     nsresult result = aSelection->GetIsCollapsed(&isCollapsed);
 
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
 
     if (isCollapsed)
     {
@@ -110,7 +110,7 @@ NS_IMETHODIMP TypeInState::NotifySelectionChanged(nsIDOMDocument *, nsISelection
 
       result = nsEditor::GetStartNodeAndOffset(aSelection, getter_AddRefs(selNode), &selOffset);
 
-      if (NS_FAILED(result)) return result;
+      NS_ENSURE_SUCCESS(result, result);
 
       if (selNode && selNode == mLastSelectionContainer && selOffset == mLastSelectionOffset)
       {
diff --git a/editor/libeditor/html/nsHTMLAbsPosition.cpp b/editor/libeditor/html/nsHTMLAbsPosition.cpp
index fc6dcdd4571..412185649f6 100644
--- a/editor/libeditor/html/nsHTMLAbsPosition.cpp
+++ b/editor/libeditor/html/nsHTMLAbsPosition.cpp
@@ -81,7 +81,7 @@ nsHTMLEditor::AbsolutePositionSelection(PRBool aEnabled)
   // Find out if the selection is collapsed:
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   nsTextRulesInfo ruleInfo(aEnabled ?
@@ -100,7 +100,7 @@ nsHTMLEditor::GetAbsolutelyPositionedSelectionContainer(nsIDOMElement **_retval)
 {
   nsCOMPtr<nsIDOMElement> element;
   nsresult res = GetSelectionContainer(getter_AddRefs(element));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsAutoString positionStr;
   nsCOMPtr<nsIDOMNode> node = do_QueryInterface(element);
@@ -109,13 +109,13 @@ nsHTMLEditor::GetAbsolutelyPositionedSelectionContainer(nsIDOMElement **_retval)
   while (!resultNode && !nsEditor::NodeIsType(node, nsEditProperty::html)) {
     res = mHTMLCSSUtils->GetComputedProperty(node, nsEditProperty::cssPosition,
                                              positionStr);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (positionStr.EqualsLiteral("absolute"))
       resultNode = node;
     else {
       nsCOMPtr<nsIDOMNode> parentNode;
       res = node->GetParentNode(getter_AddRefs(parentNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       node.swap(parentNode);
     }
   }
@@ -159,7 +159,7 @@ nsHTMLEditor::RelativeChangeElementZIndex(nsIDOMElement * aElement,
 
   PRInt32 zIndex;
   nsresult res = GetElementZIndex(aElement, &zIndex);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   zIndex = NS_MAX(zIndex + aChange, 0);
   SetElementZIndex(aElement, zIndex);
@@ -197,7 +197,7 @@ nsHTMLEditor::RelativeChangeZIndex(PRInt32 aChange)
   // Find out if the selection is collapsed:
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   nsTextRulesInfo ruleInfo((aChange < 0) ? nsTextEditRules::kDecreaseZIndex:
                                            nsTextEditRules::kIncreaseZIndex);
@@ -219,13 +219,13 @@ nsHTMLEditor::GetElementZIndex(nsIDOMElement * aElement,
   nsresult res = mHTMLCSSUtils->GetSpecifiedProperty(aElement,
                                                      nsEditProperty::cssZIndex,
                                                      zIndexStr);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (zIndexStr.EqualsLiteral("auto")) {
     // we have to look at the positioned ancestors
     // cf. CSS 2 spec section 9.9.1
     nsCOMPtr<nsIDOMNode> parentNode;
     res = aElement->GetParentNode(getter_AddRefs(parentNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     nsCOMPtr<nsIDOMNode> node = parentNode;
     nsAutoString positionStr;
     while (node && 
@@ -234,17 +234,17 @@ nsHTMLEditor::GetElementZIndex(nsIDOMElement * aElement,
       res = mHTMLCSSUtils->GetComputedProperty(node,
                                                nsEditProperty::cssPosition,
                                                positionStr);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (positionStr.EqualsLiteral("absolute")) {
         // ah, we found one, what's its z-index ? If its z-index is auto,
         // we have to continue climbing the document's tree
         res = mHTMLCSSUtils->GetComputedProperty(node,
                                                  nsEditProperty::cssZIndex,
                                                  zIndexStr);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       res = node->GetParentNode(getter_AddRefs(parentNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       node = parentNode;
     }
   }
@@ -293,7 +293,7 @@ nsHTMLEditor::RefreshGrabber()
                                          mPositionedObjectMarginLeft,
                                          mPositionedObjectMarginTop);
 
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   SetAnonymousElementPosition(mPositionedObjectX+12,
                               mPositionedObjectY-14,
@@ -306,7 +306,7 @@ nsHTMLEditor::HideGrabber()
 {
   nsresult res =
     mAbsolutelyPositionedObject->RemoveAttribute(NS_LITERAL_STRING("_moz_abspos"));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   mAbsolutelyPositionedObject = nsnull;
   NS_ENSURE_TRUE(mGrabber, NS_ERROR_NULL_POINTER);
@@ -344,11 +344,11 @@ nsHTMLEditor::ShowGrabberOnElement(nsIDOMElement * aElement)
 
   nsAutoString classValue;
   nsresult res = CheckPositionedElementBGandFG(aElement, classValue);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   res = aElement->SetAttribute(NS_LITERAL_STRING("_moz_abspos"),
                                classValue);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // first, let's keep track of that element...
   mAbsolutelyPositionedObject = aElement;
@@ -467,7 +467,7 @@ nsresult
 nsHTMLEditor::SetFinalPosition(PRInt32 aX, PRInt32 aY)
 {
   nsresult res = EndMoving();
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // we have now to set the new width and height of the resized object
   // we don't set the x and y position because we don't control that in
@@ -552,15 +552,15 @@ nsHTMLEditor::AbsolutelyPositionElement(nsIDOMElement * aElement,
     // container
     nsCOMPtr<nsIDOMNode> parentNode;
     res = aElement->GetParentNode(getter_AddRefs(parentNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     nsCOMPtr<nsIDOMNodeList> childNodes;
     res = parentNode->GetChildNodes(getter_AddRefs(childNodes));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!childNodes) return NS_ERROR_NULL_POINTER;
     PRUint32 childCount;
     res = childNodes->GetLength(&childCount);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     if (childCount == 1) {
       nsCOMPtr<nsIDOMNode> brNode;
@@ -592,12 +592,12 @@ nsHTMLEditor::AbsolutelyPositionElement(nsIDOMElement * aElement,
 
     PRBool hasStyleOrIdOrClass;
     res = HasStyleOrIdOrClass(aElement, &hasStyleOrIdOrClass);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!hasStyleOrIdOrClass && nsHTMLEditUtils::IsDiv(aElement)) {
       nsCOMPtr<nsIHTMLEditRules> htmlRules = do_QueryInterface(mRules);
       if (!htmlRules) return NS_ERROR_FAILURE;
       res = htmlRules->MakeSureElemStartsOrEndsOnCR(aElement);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = RemoveContainer(aElement);
     }
   }
@@ -680,52 +680,52 @@ nsHTMLEditor::CheckPositionedElementBGandFG(nsIDOMElement * aElement,
     mHTMLCSSUtils->GetComputedProperty(aElement,
                                        nsEditProperty::cssBackgroundImage,
                                        bgImageStr);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (bgImageStr.EqualsLiteral("none")) {
     nsAutoString bgColorStr;
     res =
       mHTMLCSSUtils->GetComputedProperty(aElement,
                                          nsEditProperty::cssBackgroundColor,
                                          bgColorStr);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (bgColorStr.EqualsLiteral("transparent")) {
 
       nsCOMPtr<nsIDOMViewCSS> viewCSS;
       res = mHTMLCSSUtils->GetDefaultViewCSS(aElement, getter_AddRefs(viewCSS));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       nsCOMPtr<nsIDOMCSSStyleDeclaration> cssDecl;
       res = viewCSS->GetComputedStyle(aElement, EmptyString(), getter_AddRefs(cssDecl));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // from these declarations, get the one we want and that one only
       nsCOMPtr<nsIDOMCSSValue> colorCssValue;
       res = cssDecl->GetPropertyCSSValue(NS_LITERAL_STRING("color"), getter_AddRefs(colorCssValue));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       PRUint16 type;
       res = colorCssValue->GetCssValueType(&type);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (nsIDOMCSSValue::CSS_PRIMITIVE_VALUE == type) {
         nsCOMPtr<nsIDOMCSSPrimitiveValue> val = do_QueryInterface(colorCssValue);
         res = val->GetPrimitiveType(&type);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (nsIDOMCSSPrimitiveValue::CSS_RGBCOLOR == type) {
           nsCOMPtr<nsIDOMRGBColor> rgbColor;
           res = val->GetRGBColorValue(getter_AddRefs(rgbColor));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           nsCOMPtr<nsIDOMCSSPrimitiveValue> red, green, blue;
           float r, g, b;
           res = rgbColor->GetRed(getter_AddRefs(red));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = rgbColor->GetGreen(getter_AddRefs(green));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = rgbColor->GetBlue(getter_AddRefs(blue));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = red->GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, &r);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = green->GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, &g);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = blue->GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, &b);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           if (r >= BLACK_BG_RGB_TRIGGER &&
               g >= BLACK_BG_RGB_TRIGGER &&
               b >= BLACK_BG_RGB_TRIGGER)
diff --git a/editor/libeditor/html/nsHTMLAnonymousUtils.cpp b/editor/libeditor/html/nsHTMLAnonymousUtils.cpp
index 2ce426515e7..c7a07b073f0 100644
--- a/editor/libeditor/html/nsHTMLAnonymousUtils.cpp
+++ b/editor/libeditor/html/nsHTMLAnonymousUtils.cpp
@@ -83,7 +83,7 @@ static PRInt32 GetCSSFloatValue(nsIDOMCSSStyleDeclaration * aDecl,
     case nsIDOMCSSPrimitiveValue::CSS_PX:
       // the value is in pixels, just get it
       res = val->GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_PX, &f);
-      if (NS_FAILED(res)) return 0;
+      NS_ENSURE_SUCCESS(res, 0);
       break;
     case nsIDOMCSSPrimitiveValue::CSS_IDENT: {
       // the value is keyword, we have to map these keywords into
@@ -163,7 +163,7 @@ nsHTMLEditor::CreateAnonymousElement(const nsAString & aTag, nsIDOMNode *  aPare
   // Create a new node through the element factory
   nsCOMPtr<nsIContent> newContent;
   nsresult res = CreateHTMLContent(aTag, getter_AddRefs(newContent));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMElement> newElement = do_QueryInterface(newContent);
   if (!newElement)
@@ -173,14 +173,14 @@ nsHTMLEditor::CreateAnonymousElement(const nsAString & aTag, nsIDOMNode *  aPare
   if (aIsCreatedHidden) {
     res = newElement->SetAttribute(NS_LITERAL_STRING("class"),
                                    NS_LITERAL_STRING("hidden"));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   // add an _moz_anonclass attribute if needed
   if (!aAnonClass.IsEmpty()) {
     res = newElement->SetAttribute(NS_LITERAL_STRING("_moz_anonclass"),
                                    aAnonClass);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   {
@@ -293,12 +293,12 @@ nsHTMLEditor::CheckSelectionStateForAnonymousButtons(nsISelection * aSelection)
   // let's get the containing element of the selection
   nsresult res  = GetSelectionContainer(getter_AddRefs(focusElement));
   if (!focusElement) return NS_OK;
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // what's its tag?
   nsAutoString focusTagName;
   res = focusElement->GetTagName(focusTagName);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   ToLowerCase(focusTagName);
   nsCOMPtr<nsIAtom> focusTagAtom = do_GetAtom(focusTagName);
 
@@ -307,7 +307,7 @@ nsHTMLEditor::CheckSelectionStateForAnonymousButtons(nsISelection * aSelection)
     // Absolute Positioning support is enabled, is the selection contained
     // in an absolutely positioned element ?
     res = GetAbsolutelyPositionedSelectionContainer(getter_AddRefs(absPosElement));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   nsCOMPtr<nsIDOMElement> cellElement;
@@ -317,7 +317,7 @@ nsHTMLEditor::CheckSelectionStateForAnonymousButtons(nsISelection * aSelection)
     res = GetElementOrParentByTagName(NS_LITERAL_STRING("td"),
                                       nsnull,
                                       getter_AddRefs(cellElement));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   if (mIsObjectResizingEnabled && cellElement) {
@@ -351,21 +351,21 @@ nsHTMLEditor::CheckSelectionStateForAnonymousButtons(nsISelection * aSelection)
   if (mIsAbsolutelyPositioningEnabled && mAbsolutelyPositionedObject &&
       absPosElement != mAbsolutelyPositionedObject) {
     res = HideGrabber();
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     NS_ASSERTION(!mAbsolutelyPositionedObject, "HideGrabber failed");
   }
 
   if (mIsObjectResizingEnabled && mResizedObject &&
       mResizedObject != focusElement) {
     res = HideResizers();
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     NS_ASSERTION(!mResizedObject, "HideResizers failed");
   }
 
   if (mIsInlineTableEditingEnabled && mInlineEditedCell &&
       mInlineEditedCell != cellElement) {
     res = HideInlineTableEditingUI();
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     NS_ASSERTION(!mInlineEditedCell, "HideInlineTableEditingUI failed");
   }
 
@@ -379,7 +379,7 @@ nsHTMLEditor::CheckSelectionStateForAnonymousButtons(nsISelection * aSelection)
       res = RefreshResizers();
     else
       res = ShowResizers(focusElement);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   if (mIsAbsolutelyPositioningEnabled && absPosElement &&
@@ -388,7 +388,7 @@ nsHTMLEditor::CheckSelectionStateForAnonymousButtons(nsISelection * aSelection)
       res = RefreshGrabber();
     else
       res = ShowGrabberOnElement(absPosElement);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   if (mIsInlineTableEditingEnabled && cellElement &&
@@ -418,7 +418,7 @@ nsHTMLEditor::GetPositionAndDimensions(nsIDOMElement * aElement,
   // Is the element positioned ? let's check the cheap way first...
   PRBool isPositioned = PR_FALSE;
   nsresult res = aElement->HasAttribute(NS_LITERAL_STRING("_moz_abspos"), &isPositioned);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!isPositioned) {
     // hmmm... the expensive way now...
     nsAutoString positionStr;
@@ -438,7 +438,7 @@ nsHTMLEditor::GetPositionAndDimensions(nsIDOMElement * aElement,
     nsCOMPtr<nsIDOMCSSStyleDeclaration> cssDecl;
     // Get the all the computed css styles attached to the element node
     res = viewCSS->GetComputedStyle(aElement, EmptyString(), getter_AddRefs(cssDecl));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     aBorderLeft = GetCSSFloatValue(cssDecl, NS_LITERAL_STRING("border-left-width"));
     aBorderTop  = GetCSSFloatValue(cssDecl, NS_LITERAL_STRING("border-top-width"));
@@ -460,7 +460,7 @@ nsHTMLEditor::GetPositionAndDimensions(nsIDOMElement * aElement,
     GetElementOrigin(aElement, aX, aY);
 
     res = nsElement->GetOffsetWidth(&aW);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = nsElement->GetOffsetHeight(&aH);
 
     aBorderLeft = 0;
diff --git a/editor/libeditor/html/nsHTMLCSSUtils.cpp b/editor/libeditor/html/nsHTMLCSSUtils.cpp
index b93bb67e4c9..565ae9cc14c 100644
--- a/editor/libeditor/html/nsHTMLCSSUtils.cpp
+++ b/editor/libeditor/html/nsHTMLCSSUtils.cpp
@@ -317,7 +317,7 @@ nsHTMLCSSUtils::Init(nsHTMLEditor *aEditor)
     do_GetService(NS_PREFSERVICE_CONTRACTID, &result);
   if (NS_SUCCEEDED(result) && prefBranch) {
     result = prefBranch->GetBoolPref("editor.use_css", &mIsCSSPrefChecked);
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
   }
   return result;
 }
@@ -542,7 +542,7 @@ nsHTMLCSSUtils::GetComputedProperty(nsIDOMNode *aNode, nsIAtom *aProperty,
 {
   nsCOMPtr<nsIDOMViewCSS> viewCSS = nsnull;
   nsresult res = GetDefaultViewCSS(aNode, getter_AddRefs(viewCSS));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   return GetCSSInlinePropertyBase(aNode, aProperty, aValue, viewCSS, COMPUTED_STYLE_TYPE);
 }
@@ -558,7 +558,7 @@ nsHTMLCSSUtils::GetCSSInlinePropertyBase(nsIDOMNode *aNode, nsIAtom *aProperty,
 
   nsCOMPtr<nsIDOMElement>element;
   nsresult res = GetElementContainerOrSelf(aNode, getter_AddRefs(element));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   switch (aStyleType) {
     case COMPUTED_STYLE_TYPE:
@@ -571,7 +571,7 @@ nsHTMLCSSUtils::GetCSSInlinePropertyBase(nsIDOMNode *aNode, nsIAtom *aProperty,
         if (NS_FAILED(res) || !cssDecl) return res;
         // from these declarations, get the one we want and that one only
         res = cssDecl->GetPropertyValue(propString, value);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         aValue.Assign(value);
       }
       break;
@@ -584,7 +584,7 @@ nsHTMLCSSUtils::GetCSSInlinePropertyBase(nsIDOMNode *aNode, nsIAtom *aProperty,
         nsAutoString value, propString;
         aProperty->ToString(propString);
         res = cssDecl->GetPropertyValue(propString, value);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         aValue.Assign(value);
       }
       break;
@@ -597,7 +597,7 @@ nsHTMLCSSUtils::GetDefaultViewCSS(nsIDOMNode *aNode, nsIDOMViewCSS **aViewCSS)
 {
   nsCOMPtr<nsIDOMElement>element;
   nsresult res = GetElementContainerOrSelf(aNode, getter_AddRefs(element));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // if we have an element node
   if (element) {
@@ -605,13 +605,13 @@ nsHTMLCSSUtils::GetDefaultViewCSS(nsIDOMNode *aNode, nsIDOMViewCSS **aViewCSS)
     nsCOMPtr<nsIDOMDocument> doc;
     nsCOMPtr<nsIDOMNode> node = do_QueryInterface(element);
     res = node->GetOwnerDocument(getter_AddRefs(doc));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (doc) {
       nsCOMPtr<nsIDOMDocumentView> documentView = do_QueryInterface(doc);
       nsCOMPtr<nsIDOMAbstractView> abstractView;
       // from the document, get the abtractView
       res = documentView->GetDefaultView(getter_AddRefs(abstractView));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (abstractView) {
         // from the abstractView, get the CSS view
         CallQueryInterface(abstractView, aViewCSS);
@@ -645,7 +645,7 @@ nsHTMLCSSUtils::RemoveCSSInlineStyle(nsIDOMNode *aNode, nsIAtom *aProperty, cons
 
   // remove the property from the style attribute
   nsresult res = RemoveCSSProperty(elem, aProperty, aPropertyValue, PR_FALSE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   if (nsEditor::NodeIsType(aNode, nsEditProperty::span)) {
     nsCOMPtr<nsIContent> content = do_QueryInterface(aNode);
@@ -654,13 +654,13 @@ nsHTMLCSSUtils::RemoveCSSInlineStyle(nsIDOMNode *aNode, nsIAtom *aProperty, cons
     if (0 == attrCount) {
       // no more attributes on this span, let's remove the element
       res = mHTMLEditor->RemoveContainer(aNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     else if (1 == attrCount) {
       // incredible hack in case the only remaining attribute is a _moz_dirty...
       if (content->GetAttrNameAt(0)->Equals(nsEditProperty::mozdirty)) {
         res = mHTMLEditor->RemoveContainer(aNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
   }
@@ -682,26 +682,26 @@ nsHTMLCSSUtils::GetDefaultBackgroundColor(nsAString & aColor)
   nsresult result;
   nsCOMPtr<nsIPrefBranch> prefBranch =
     do_GetService(NS_PREFSERVICE_CONTRACTID, &result);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   aColor.AssignLiteral("#ffffff");
   nsXPIDLCString returnColor;
   if (prefBranch) {
     PRBool useCustomColors;
     result = prefBranch->GetBoolPref("editor.use_custom_colors", &useCustomColors);
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (useCustomColors) {
       result = prefBranch->GetCharPref("editor.background_color",
                                        getter_Copies(returnColor));
-      if (NS_FAILED(result)) return result;
+      NS_ENSURE_SUCCESS(result, result);
     }
     else {
       PRBool useSystemColors;
       result = prefBranch->GetBoolPref("browser.display.use_system_colors", &useSystemColors);
-      if (NS_FAILED(result)) return result;
+      NS_ENSURE_SUCCESS(result, result);
       if (!useSystemColors) {
         result = prefBranch->GetCharPref("browser.display.background_color",
                                          getter_Copies(returnColor));
-        if (NS_FAILED(result)) return result;
+        NS_ENSURE_SUCCESS(result, result);
       }
     }
   }
@@ -718,13 +718,13 @@ nsHTMLCSSUtils::GetDefaultLengthUnit(nsAString & aLengthUnit)
   nsresult result;
   nsCOMPtr<nsIPrefBranch> prefBranch =
     do_GetService(NS_PREFSERVICE_CONTRACTID, &result);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   aLengthUnit.AssignLiteral("px");
   if (NS_SUCCEEDED(result) && prefBranch) {
     nsXPIDLCString returnLengthUnit;
     result = prefBranch->GetCharPref("editor.css.default_length_unit",
                                      getter_Copies(returnLengthUnit));
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (returnLengthUnit) {
       CopyASCIItoUTF16(returnLengthUnit, aLengthUnit);
     }
@@ -1009,7 +1009,7 @@ nsHTMLCSSUtils::SetCSSEquivalentToHTMLStyle(nsIDOMNode * aNode,
       nsCOMPtr<nsIDOMElement> theElement = do_QueryInterface(aNode);
       res = SetCSSProperty(theElement, cssPropertyArray[index],
                            cssValueArray[index], aSuppressTransaction);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   return NS_OK;
@@ -1044,7 +1044,7 @@ nsHTMLCSSUtils::RemoveCSSEquivalentToHTMLStyle(nsIDOMNode * aNode,
                               cssPropertyArray[index],
                               cssValueArray[index],
                               aSuppressTransaction);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   return NS_OK;
@@ -1059,9 +1059,9 @@ nsHTMLCSSUtils::HasClassOrID(nsIDOMElement * aElement, PRBool & aReturn)
   aReturn = PR_FALSE;
 
   nsresult res = mHTMLEditor->GetAttributeValue(aElement,  NS_LITERAL_STRING("class"), classVal, &isClassSet);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = mHTMLEditor->GetAttributeValue(aElement,  NS_LITERAL_STRING("id"), idVal, &isIdSet);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // we need to make sure that if the element has an id or a class attribute,
   // the attribute is not the empty string
@@ -1084,7 +1084,7 @@ nsHTMLCSSUtils::GetCSSEquivalentToHTMLInlineStyleSet(nsIDOMNode * aNode,
   aValueString.Truncate();
   nsCOMPtr<nsIDOMElement> theElement;
   nsresult res = GetElementContainerOrSelf(aNode, getter_AddRefs(theElement));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   if (theElement && IsCSSEditableProperty(theElement, aHTMLProperty, aAttribute)) {
     // Yes, the requested HTML style has a CSS equivalence in this implementation
@@ -1092,7 +1092,7 @@ nsHTMLCSSUtils::GetCSSEquivalentToHTMLInlineStyleSet(nsIDOMNode * aNode,
     nsCOMPtr<nsIDOMViewCSS> viewCSS = nsnull;
     if (COMPUTED_STYLE_TYPE == aStyleType) {
       res = GetDefaultViewCSS(theElement, getter_AddRefs(viewCSS));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     nsTArray<nsIAtom*> cssPropertyArray;
     nsTArray<nsString> cssValueArray;
@@ -1107,7 +1107,7 @@ nsHTMLCSSUtils::GetCSSEquivalentToHTMLInlineStyleSet(nsIDOMNode * aNode,
       // retrieve the specified/computed value of the property
       res = GetCSSInlinePropertyBase(theElement, cssPropertyArray[index],
                                      valueString, viewCSS, aStyleType);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // append the value to aValueString (possibly with a leading whitespace)
       if (index) aValueString.Append(PRUnichar(' '));
       aValueString.Append(valueString);
@@ -1140,7 +1140,7 @@ nsHTMLCSSUtils::IsCSSEquivalentToHTMLInlineStyleSet(nsIDOMNode * aNode,
     // get the value of the CSS equivalent styles
     nsresult res = GetCSSEquivalentToHTMLInlineStyleSet(node, aHTMLProperty, aHTMLAttribute,
                                                         valueString, aStyleType);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // early way out if we can
     if (valueString.IsEmpty()) return NS_OK;
@@ -1274,7 +1274,7 @@ nsHTMLCSSUtils::IsCSSEquivalentToHTMLInlineStyleSet(nsIDOMNode * aNode,
       // that means that we have to look at ancestors of node to see if they are underlined
       nsCOMPtr<nsIDOMNode> tmp;
       res = node->GetParentNode(getter_AddRefs(tmp));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       nsCOMPtr<nsIDOMElement> element = do_QueryInterface(tmp);
       node = element;  // set to null if it's not a dom element
     }
@@ -1402,7 +1402,7 @@ nsHTMLCSSUtils::GetElementContainerOrSelf(nsIDOMNode * aNode, nsIDOMElement ** a
   PRUint16 type;
   nsresult res;
   res = node->GetNodeType(&type);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   if (nsIDOMNode::DOCUMENT_NODE == type) {
     return NS_ERROR_NULL_POINTER;
@@ -1412,10 +1412,10 @@ nsHTMLCSSUtils::GetElementContainerOrSelf(nsIDOMNode * aNode, nsIDOMElement ** a
   while (node && nsIDOMNode::ELEMENT_NODE != type) {
     parentNode = node;
     res = parentNode->GetParentNode(getter_AddRefs(node));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (node) {
       res = node->GetNodeType(&type);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   NS_ASSERTION(node, "we reached a null node ancestor !");
diff --git a/editor/libeditor/html/nsHTMLDataTransfer.cpp b/editor/libeditor/html/nsHTMLDataTransfer.cpp
index 054d2f0fdfb..b6016106584 100644
--- a/editor/libeditor/html/nsHTMLDataTransfer.cpp
+++ b/editor/libeditor/html/nsHTMLDataTransfer.cpp
@@ -184,24 +184,24 @@ NS_IMETHODIMP nsHTMLEditor::LoadHTML(const nsAString & aInputString)
   // Get selection
   nsCOMPtr<nsISelection>selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   nsTextRulesInfo ruleInfo(nsTextEditRules::kLoadHTML);
   PRBool cancel, handled;
   res = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (cancel) return NS_OK; // rules canceled the operation
   if (!handled)
   {
     PRBool isCollapsed;
     res = selection->GetIsCollapsed(&isCollapsed);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // Delete Selection, but only if it isn't collapsed, see bug #106269
     if (!isCollapsed) 
     {
       res = DeleteSelection(eNone);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
 
     // Get the first range in the selection, for context:
@@ -274,7 +274,7 @@ nsHTMLEditor::InsertHTMLWithContext(const nsAString & aInputString,
   nsresult res;
   nsCOMPtr<nsISelection>selection;
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // create a dom document fragment that represents the structure to paste
   nsCOMPtr<nsIDOMNode> fragmentAsNode, streamStartParent, streamEndParent;
@@ -297,7 +297,7 @@ nsHTMLEditor::InsertHTMLWithContext(const nsAString & aInputString,
     // fetch the paste insertion point from our selection
     res = GetStartNodeAndOffset(selection, getter_AddRefs(targetNode), &targetOffset);
     if (!targetNode) res = NS_ERROR_FAILURE;
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   else
   {
@@ -411,7 +411,7 @@ nsHTMLEditor::InsertHTMLWithContext(const nsAString & aInputString,
   nsTextRulesInfo ruleInfo(nsTextEditRules::kInsertElement);
   PRBool cancel, handled;
   res = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (cancel) return NS_OK; // rules canceled the operation
   if (!handled)
   {
@@ -419,7 +419,7 @@ nsHTMLEditor::InsertHTMLWithContext(const nsAString & aInputString,
     // refresh our memory...
     res = GetStartNodeAndOffset(selection, getter_AddRefs(parentNode), &offsetOfNewNode);
     if (!parentNode) res = NS_ERROR_FAILURE;
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // Adjust position based on the first node we are going to insert.
     NormalizeEOLInsertPosition(nodeList[0], address_of(parentNode), &offsetOfNewNode);
@@ -432,7 +432,7 @@ nsHTMLEditor::InsertHTMLWithContext(const nsAString & aInputString,
         !IsVisBreak(wsObj.mEndReasonNode) )
     {
       res = DeleteNode(wsObj.mEndReasonNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     
     // remeber if we are in a link.  
@@ -443,9 +443,9 @@ nsHTMLEditor::InsertHTMLWithContext(const nsAString & aInputString,
     {
       nsCOMPtr<nsIDOMNode> temp;
       res = SplitNodeDeep(parentNode, parentNode, offsetOfNewNode, &offsetOfNewNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = parentNode->GetParentNode(getter_AddRefs(temp));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       parentNode = temp;
     }
 
@@ -654,7 +654,7 @@ nsHTMLEditor::InsertHTMLWithContext(const nsAString & aInputString,
       if (!nsHTMLEditUtils::IsTable(lastInsertNode))
       {
         res = GetLastEditableLeaf(lastInsertNode, address_of(selNode));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         tmp = selNode;
         while (tmp && (tmp != lastInsertNode))
         {
@@ -672,14 +672,14 @@ nsHTMLEditor::InsertHTMLWithContext(const nsAString & aInputString,
       if (IsTextNode(selNode) || (IsContainer(selNode) && !nsHTMLEditUtils::IsTable(selNode)))  
       {
         res = GetLengthOfDOMNode(selNode, (PRUint32&)selOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       else // we need to find a container for selection.  Look up.
       {
         tmp = selNode;
         res = GetNodeLocation(tmp, address_of(selNode), &selOffset);
         ++selOffset;  // want to be *after* last leaf node in paste
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       
       // make sure we don't end up with selection collapsed after an invisible break node
@@ -687,7 +687,7 @@ nsHTMLEditor::InsertHTMLWithContext(const nsAString & aInputString,
       PRInt32 outVisOffset=0;
       PRInt16 visType=0;
       res = wsRunObj.PriorVisibleNode(selNode, selOffset, address_of(visNode), &outVisOffset, &visType);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (visType == nsWSRunObject::eBreak)
       {
         // we are after a break.  Is it visible?  Despite the name, 
@@ -702,7 +702,7 @@ nsHTMLEditor::InsertHTMLWithContext(const nsAString & aInputString,
           // we want to be inside any inline style prior to break
           nsWSRunObject wsRunObj(this, selNode, selOffset);
           res = wsRunObj.PriorVisibleNode(selNode, selOffset, address_of(visNode), &outVisOffset, &visType);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           if (visType == nsWSRunObject::eText ||
               visType == nsWSRunObject::eNormalWS)
           {
@@ -731,9 +731,9 @@ nsHTMLEditor::InsertHTMLWithContext(const nsAString & aInputString,
         nsCOMPtr<nsIDOMNode> leftLink;
         PRInt32 linkOffset;
         res = SplitNodeDeep(link, selNode, selOffset, &linkOffset, PR_TRUE, address_of(leftLink));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = GetNodeLocation(leftLink, address_of(selNode), &selOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         selection->Collapse(selNode, selOffset+1);
       }
     }
@@ -1485,7 +1485,7 @@ NS_IMETHODIMP nsHTMLEditor::InsertFromDrop(nsIDOMEvent* aDropEvent)
   nsresult rv;
   nsCOMPtr<nsIDragService> dragService = 
            do_GetService("@mozilla.org/widget/dragservice;1", &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsIDragSession> dragSession;
   dragService->GetCurrentSession(getter_AddRefs(dragSession)); 
@@ -1499,17 +1499,17 @@ NS_IMETHODIMP nsHTMLEditor::InsertFromDrop(nsIDOMEvent* aDropEvent)
   // around with cfhtml if we do.
   PRBool bHavePrivateHTMLFlavor = PR_FALSE;
   rv = dragSession->IsDataFlavorSupported(kHTMLContext, &bHavePrivateHTMLFlavor);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   // Get the nsITransferable interface for getting the data from the drop
   nsCOMPtr<nsITransferable> trans;
   rv = PrepareHTMLTransferable(getter_AddRefs(trans), bHavePrivateHTMLFlavor);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!trans) return NS_OK;  // NS_ERROR_FAILURE; SHOULD WE FAIL?
 
   PRUint32 numItems = 0; 
   rv = dragSession->GetNumDropItems(&numItems);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // Combine any deletion and drop insertion into one transaction
   nsAutoEditBatch beginBatching(this);
@@ -1522,14 +1522,14 @@ NS_IMETHODIMP nsHTMLEditor::InsertFromDrop(nsIDOMEvent* aDropEvent)
   // Source doc is null if source is *not* the current editor document
   nsCOMPtr<nsIDOMDocument> srcdomdoc;
   rv = dragSession->GetSourceDocument(getter_AddRefs(srcdomdoc));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   PRUint32 i; 
   PRBool doPlaceCaret = PR_TRUE;
   for (i = 0; i < numItems; ++i)
   {
     rv = dragSession->GetData(trans, i);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
     if (!trans) return NS_OK; // NS_ERROR_FAILURE; Should we fail?
 
     // get additional html copy hints, if present
@@ -1591,24 +1591,24 @@ NS_IMETHODIMP nsHTMLEditor::InsertFromDrop(nsIDOMEvent* aDropEvent)
       // Current doc is destination
       nsCOMPtr<nsIDOMDocument>destdomdoc; 
       rv = GetDocument(getter_AddRefs(destdomdoc)); 
-      if (NS_FAILED(rv)) return rv;
+      NS_ENSURE_SUCCESS(rv, rv);
 
       nsCOMPtr<nsISelection> selection;
       rv = GetSelection(getter_AddRefs(selection));
-      if (NS_FAILED(rv)) return rv;
+      NS_ENSURE_SUCCESS(rv, rv);
       if (!selection) return NS_ERROR_FAILURE;
 
       PRBool isCollapsed;
       rv = selection->GetIsCollapsed(&isCollapsed);
-      if (NS_FAILED(rv)) return rv;
+      NS_ENSURE_SUCCESS(rv, rv);
       
       // Parent and offset under the mouse cursor
       rv = nsuiEvent->GetRangeParent(getter_AddRefs(newSelectionParent));
-      if (NS_FAILED(rv)) return rv;
+      NS_ENSURE_SUCCESS(rv, rv);
       if (!newSelectionParent) return NS_ERROR_FAILURE;
 
       rv = nsuiEvent->GetRangeOffset(&newSelectionOffset);
-      if (NS_FAILED(rv)) return rv;
+      NS_ENSURE_SUCCESS(rv, rv);
 
       // XXX: This userSelectNode code is a workaround for bug 195957.
       //
@@ -1631,7 +1631,7 @@ NS_IMETHODIMP nsHTMLEditor::InsertFromDrop(nsIDOMEvent* aDropEvent)
         rv = GetNodeLocation(userSelectNode, address_of(newSelectionParent),
                              &newSelectionOffset);
 
-        if (NS_FAILED(rv)) return rv;
+        NS_ENSURE_SUCCESS(rv, rv);
         if (!newSelectionParent) return NS_ERROR_FAILURE;
       }
 
@@ -1720,7 +1720,7 @@ nsHTMLEditor::PutDragDataInTransferable(nsITransferable **aTransferable)
   *aTransferable = nsnull;
   nsCOMPtr<nsIDocumentEncoder> docEncoder;
   nsresult rv = SetupDocEncoder(getter_AddRefs(docEncoder));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   NS_ENSURE_TRUE(docEncoder, NS_ERROR_FAILURE);
 
   // grab a string
@@ -1731,13 +1731,13 @@ nsHTMLEditor::PutDragDataInTransferable(nsITransferable **aTransferable)
   {
     // encode the selection as html with contextual info
     rv = docEncoder->EncodeToStringWithContext(parents, info, buffer);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
   else
   {
     // encode the selection
     rv = docEncoder->EncodeToString(buffer);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
 
   // if we have an empty string, we're done; otherwise continue
@@ -1749,7 +1749,7 @@ nsHTMLEditor::PutDragDataInTransferable(nsITransferable **aTransferable)
   dataWrapper = do_CreateInstance(NS_SUPPORTS_STRING_CONTRACTID, &rv);
   NS_ENSURE_SUCCESS(rv, rv);
   rv = dataWrapper->SetData(buffer);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   /* create html flavor transferable */
   nsCOMPtr<nsITransferable> trans = do_CreateInstance("@mozilla.org/widget/transferable;1");
@@ -1759,14 +1759,14 @@ nsHTMLEditor::PutDragDataInTransferable(nsITransferable **aTransferable)
   {
     // Add the unicode flavor to the transferable
     rv = trans->AddDataFlavor(kUnicodeMime);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
 
     // QI the data object an |nsISupports| so that when the transferable holds
     // onto it, it will addref the correct interface.
     nsCOMPtr<nsISupports> genericDataObj(do_QueryInterface(dataWrapper));
     rv = trans->SetTransferData(kUnicodeMime, genericDataObj,
                                 buffer.Length() * sizeof(PRUnichar));
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
   else
   {
@@ -1779,19 +1779,19 @@ nsHTMLEditor::PutDragDataInTransferable(nsITransferable **aTransferable)
     infoWrapper->SetData(info);
 
     rv = trans->AddDataFlavor(kHTMLMime);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
 
     nsCOMPtr<nsIFormatConverter> htmlConverter =
              do_CreateInstance("@mozilla.org/widget/htmlformatconverter;1");
     NS_ENSURE_TRUE(htmlConverter, NS_ERROR_FAILURE);
 
     rv = trans->SetConverter(htmlConverter);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
 
     nsCOMPtr<nsISupports> genericDataObj(do_QueryInterface(dataWrapper));
     rv = trans->SetTransferData(kHTMLMime, genericDataObj,
                                 buffer.Length() * sizeof(PRUnichar));
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
 
     if (!parents.IsEmpty())
     {
@@ -1993,7 +1993,7 @@ NS_IMETHODIMP nsHTMLEditor::CanPaste(PRInt32 aSelectionType, PRBool *aCanPaste)
 
   nsresult rv;
   nsCOMPtr<nsIClipboard> clipboard(do_GetService("@mozilla.org/widget/clipboard;1", &rv));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   PRBool haveFlavors;
 
@@ -2007,7 +2007,7 @@ NS_IMETHODIMP nsHTMLEditor::CanPaste(PRInt32 aSelectionType, PRBool *aCanPaste)
                                            NS_ARRAY_LENGTH(textHtmlEditorFlavors),
                                            aSelectionType, &haveFlavors);
   
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   *aCanPaste = haveFlavors;
   return NS_OK;
@@ -2080,20 +2080,20 @@ NS_IMETHODIMP nsHTMLEditor::PasteAsCitedQuotation(const nsAString & aCitation,
   // get selection
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   // give rules a chance to handle or cancel
   nsTextRulesInfo ruleInfo(nsTextEditRules::kInsertElement);
   PRBool cancel, handled;
   res = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (cancel) return NS_OK; // rules canceled the operation
   if (!handled)
   {
     nsCOMPtr<nsIDOMNode> newNode;
     res = DeleteSelectionAndCreateNode(NS_LITERAL_STRING("blockquote"), getter_AddRefs(newNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!newNode) return NS_ERROR_NULL_POINTER;
 
     // Try to set type=cite.  Ignore it if this fails.
@@ -2126,7 +2126,7 @@ NS_IMETHODIMP nsHTMLEditor::PasteAsPlaintextQuotation(PRInt32 aSelectionType)
   // Get Clipboard Service
   nsresult rv;
   nsCOMPtr<nsIClipboard> clipboard(do_GetService("@mozilla.org/widget/clipboard;1", &rv));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // Create generic Transferable for getting the data
   nsCOMPtr<nsITransferable> trans =
@@ -2304,7 +2304,7 @@ nsHTMLEditor::InsertAsPlaintextQuotation(const nsAString & aQuotedText,
   // get selection
   nsCOMPtr<nsISelection> selection;
   rv = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!selection) return NS_ERROR_NULL_POINTER;
   else
   {
@@ -2315,7 +2315,7 @@ nsHTMLEditor::InsertAsPlaintextQuotation(const nsAString & aQuotedText,
     nsTextRulesInfo ruleInfo(nsTextEditRules::kInsertElement);
     PRBool cancel, handled;
     rv = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
     if (cancel) return NS_OK; // rules canceled the operation
     if (!handled)
     {
@@ -2417,7 +2417,7 @@ nsHTMLEditor::InsertAsCitedQuotation(const nsAString & aQuotedText,
   // get selection
   nsCOMPtr<nsISelection> selection;
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   else
   {
@@ -2428,12 +2428,12 @@ nsHTMLEditor::InsertAsCitedQuotation(const nsAString & aQuotedText,
     nsTextRulesInfo ruleInfo(nsTextEditRules::kInsertElement);
     PRBool cancel, handled;
     res = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (cancel) return NS_OK; // rules canceled the operation
     if (!handled)
     {
       res = DeleteSelectionAndCreateNode(NS_LITERAL_STRING("blockquote"), getter_AddRefs(newNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!newNode) return NS_ERROR_NULL_POINTER;
 
       // Try to set type=cite.  Ignore it if this fails.
diff --git a/editor/libeditor/html/nsHTMLEditRules.cpp b/editor/libeditor/html/nsHTMLEditRules.cpp
index 337c05ed59e..e8602d9efe0 100644
--- a/editor/libeditor/html/nsHTMLEditRules.cpp
+++ b/editor/libeditor/html/nsHTMLEditRules.cpp
@@ -147,7 +147,7 @@ class nsEmptyEditableFunctor : public nsBoolDomIterFunctor
       {
         PRBool bIsEmptyNode;
         nsresult res = mHTMLEditor->IsEmptyNode(aNode, &bIsEmptyNode, PR_FALSE, PR_FALSE);
-        if (NS_FAILED(res)) return PR_FALSE;
+        NS_ENSURE_SUCCESS(res, PR_FALSE);
         if (bIsEmptyNode)
           return PR_TRUE;
       }
@@ -255,12 +255,12 @@ nsHTMLEditRules::Init(nsPlaintextEditor *aEditor)
   
   // call through to base class Init 
   res = nsTextEditRules::Init(aEditor);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // cache any prefs we care about
   nsCOMPtr<nsIPrefBranch> prefBranch =
     do_GetService(NS_PREFSERVICE_CONTRACTID, &res);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   char *returnInEmptyLIKillsList = 0;
   res = prefBranch->GetCharPref("editor.html.typing.returnInEmptyListItemClosesList",
@@ -295,7 +295,7 @@ nsHTMLEditRules::Init(nsPlaintextEditor *aEditor)
     }
     mDocChangeRange->SelectNode(rootElem);
     res = AdjustSpecialBreaks();
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   // add ourselves as a listener to edit actions
@@ -329,19 +329,19 @@ nsHTMLEditRules::BeforeEdit(PRInt32 action, nsIEditor::EDirection aDirection)
     // get selection
     nsCOMPtr<nsISelection>selection;
     nsresult res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   
     // get the selection start location
     nsCOMPtr<nsIDOMNode> selStartNode, selEndNode;
     PRInt32 selOffset;
     res = mHTMLEditor->GetStartNodeAndOffset(selection, getter_AddRefs(selStartNode), &selOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     mRangeItem.startNode = selStartNode;
     mRangeItem.startOffset = selOffset;
 
     // get the selection end location
     res = mHTMLEditor->GetEndNodeAndOffset(selection, getter_AddRefs(selEndNode), &selOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     mRangeItem.endNode = selEndNode;
     mRangeItem.endOffset = selOffset;
 
@@ -375,7 +375,7 @@ nsHTMLEditRules::BeforeEdit(PRInt32 action, nsIEditor::EDirection aDirection)
       if (aDirection == nsIEditor::eNext)
         selNode = selEndNode;
       res = CacheInlineStyles(selNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     
     // check that selection is in subtree defined by body node
@@ -416,7 +416,7 @@ nsHTMLEditRules::AfterEdit(PRInt32 action, nsIEditor::EDirection aDirection)
 
       nsCOMPtr<nsISelection> selection;
       nsresult res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       nsCOMPtr<nsISelectionPrivate> privateSelection(do_QueryInterface(selection));
       nsCOMPtr<nsFrameSelection> frameSelection;
       privateSelection->GetFrameSelection(getter_AddRefs(frameSelection));
@@ -438,7 +438,7 @@ nsHTMLEditRules::AfterEditInner(PRInt32 action, nsIEditor::EDirection aDirection
   
   nsCOMPtr<nsISelection>selection;
   nsresult res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   nsCOMPtr<nsIDOMNode> rangeStartParent, rangeEndParent;
   PRInt32 rangeStartOffset = 0, rangeEndOffset = 0;
@@ -462,7 +462,7 @@ nsHTMLEditRules::AfterEditInner(PRInt32 action, nsIEditor::EDirection aDirection
    
     // expand the "changed doc range" as needed
     res = PromoteRange(mDocChangeRange, action);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // if we did a ranged deletion, make sure we have a place to put caret.
     // Note we only want to do this if the overall operation was deletion,
@@ -471,19 +471,19 @@ nsHTMLEditRules::AfterEditInner(PRInt32 action, nsIEditor::EDirection aDirection
     if ((action == nsEditor::kOpDeleteSelection) && mDidRangedDelete)
     {
       res = InsertBRIfNeeded(selection);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }  
     
     // add in any needed <br>s, and remove any unneeded ones.
     res = AdjustSpecialBreaks();
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     // merge any adjacent text nodes
     if ( (action != nsEditor::kOpInsertText &&
          action != nsEditor::kOpInsertIMEText) )
     {
       res = mHTMLEditor->CollapseAdjacentTextNodes(mDocChangeRange);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     
     // replace newlines with breaks.
@@ -498,12 +498,12 @@ nsHTMLEditRules::AfterEditInner(PRInt32 action, nsIEditor::EDirection aDirection
         (action == nsHTMLEditor::kOpLoadHTML)))
     {
       res = ReplaceNewlines(mDocChangeRange);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     
     // clean up any empty nodes in the selection
     res = RemoveEmptyNodes();
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // attempt to transform any unneeded nbsp's into spaces after doing various operations
     if ((action == nsEditor::kOpInsertText) || 
@@ -514,7 +514,7 @@ nsHTMLEditRules::AfterEditInner(PRInt32 action, nsIEditor::EDirection aDirection
         (action == nsHTMLEditor::kOpLoadHTML)))
     {
       res = AdjustWhitespace(selection);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       
       // also do this for original selection endpoints. 
       nsWSRunObject(mHTMLEditor, mRangeItem.startNode, mRangeItem.startOffset).AdjustWhitespace();
@@ -541,7 +541,7 @@ nsHTMLEditRules::AfterEditInner(PRInt32 action, nsIEditor::EDirection aDirection
         (action == nsHTMLEditor::kOpLoadHTML)))
     {
       res = AdjustSelection(selection, aDirection);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
 
     // check for any styles which were removed inappropriately
@@ -552,9 +552,9 @@ nsHTMLEditRules::AfterEditInner(PRInt32 action, nsIEditor::EDirection aDirection
     {
       mHTMLEditor->mTypeInState->UpdateSelState(selection);
       res = ReapplyCachedStyles();
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = ClearCachedStyles();
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }    
   }
 
@@ -711,7 +711,7 @@ nsHTMLEditRules::DidDoAction(nsISelection *aSelection,
       return DidMakeBasicBlock(aSelection, aInfo, aResult);
     case kSetAbsolutePosition: {
       nsresult rv = DidMakeBasicBlock(aSelection, aInfo, aResult);
-      if (NS_FAILED(rv)) return rv;
+      NS_ENSURE_SUCCESS(rv, rv);
       return DidAbsolutePosition();
       }
   }
@@ -737,7 +737,7 @@ nsHTMLEditRules::GetListState(PRBool *aMixed, PRBool *aOL, PRBool *aUL, PRBool *
   
   nsCOMArray<nsIDOMNode> arrayOfNodes;
   nsresult res = GetListActionNodes(arrayOfNodes, PR_FALSE, PR_TRUE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // examine list type for nodes in selection
   PRInt32 listCount = arrayOfNodes.Count();
@@ -755,7 +755,7 @@ nsHTMLEditRules::GetListState(PRBool *aMixed, PRBool *aOL, PRBool *aUL, PRBool *
       nsCOMPtr<nsIDOMNode> parent;
       PRInt32 offset;
       res = nsEditor::GetNodeLocation(curNode, address_of(parent), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (nsHTMLEditUtils::IsUnorderedList(parent))
         *aUL = PR_TRUE;
       else if (nsHTMLEditUtils::IsOrderedList(parent))
@@ -789,7 +789,7 @@ nsHTMLEditRules::GetListItemState(PRBool *aMixed, PRBool *aLI, PRBool *aDT, PRBo
   
   nsCOMArray<nsIDOMNode> arrayOfNodes;
   nsresult res = GetListActionNodes(arrayOfNodes, PR_FALSE, PR_TRUE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // examine list type for nodes in selection
   PRInt32 listCount = arrayOfNodes.Count();
@@ -817,7 +817,7 @@ nsHTMLEditRules::GetListItemState(PRBool *aMixed, PRBool *aLI, PRBool *aDT, PRBo
       // need to look inside dl and see which types of items it has
       PRBool bDT, bDD;
       res = GetDefinitionListItemTypes(curNode, bDT, bDD);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       *aDT |= bDT;
       *aDD |= bDD;
     }
@@ -850,7 +850,7 @@ nsHTMLEditRules::GetAlignment(PRBool *aMixed, nsIHTMLEditor::EAlignment *aAlign)
   // get selection
   nsCOMPtr<nsISelection>selection;
   nsresult res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // get selection location
   nsCOMPtr<nsIDOMNode> parent;
@@ -860,14 +860,14 @@ nsHTMLEditRules::GetAlignment(PRBool *aMixed, nsIHTMLEditor::EAlignment *aAlign)
 
   PRInt32 offset, rootOffset;
   res = nsEditor::GetNodeLocation(rootElem, address_of(parent), &rootOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = mHTMLEditor->GetStartNodeAndOffset(selection, getter_AddRefs(parent), &offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // is the selection collapsed?
   PRBool bCollapsed;
   res = selection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsCOMPtr<nsIDOMNode> nodeToExamine;
   nsCOMPtr<nsISupports> isupports;
   if (bCollapsed)
@@ -891,12 +891,12 @@ nsHTMLEditRules::GetAlignment(PRBool *aMixed, nsIHTMLEditor::EAlignment *aAlign)
   {
     nsCOMArray<nsIDOMRange> arrayOfRanges;
     res = GetPromotedRanges(selection, arrayOfRanges, kAlign);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // use these ranges to construct a list of nodes to act on.
     nsCOMArray<nsIDOMNode> arrayOfNodes;
     res = GetNodesForOperation(arrayOfRanges, arrayOfNodes, kAlign, PR_TRUE);
-    if (NS_FAILED(res)) return res;                                 
+    NS_ENSURE_SUCCESS(res, res);                                 
     nodeToExamine = arrayOfNodes.SafeObjectAt(0);
   }
 
@@ -1013,7 +1013,7 @@ nsHTMLEditRules::GetIndentState(PRBool *aCanIndent, PRBool *aCanOutdent)
   // get selection
   nsCOMPtr<nsISelection>selection;
   nsresult res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));
   if (!selPriv)
     return NS_ERROR_FAILURE;
@@ -1021,7 +1021,7 @@ nsHTMLEditRules::GetIndentState(PRBool *aCanIndent, PRBool *aCanOutdent)
   // contruct a list of nodes to act on.
   nsCOMArray<nsIDOMNode> arrayOfNodes;
   res = GetNodesFromSelection(selection, kIndent, arrayOfNodes, PR_TRUE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // examine nodes in selection for blockquotes or list elements;
   // these we can outdent.  Note that we return true for canOutdent
@@ -1072,12 +1072,12 @@ nsHTMLEditRules::GetIndentState(PRBool *aCanIndent, PRBool *aCanOutdent)
     root = do_QueryInterface(rootElem);
     if (!root) return NS_ERROR_NO_INTERFACE;
     res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!selection) return NS_ERROR_NULL_POINTER;
     
     // test start parent hierarchy
     res = mHTMLEditor->GetStartNodeAndOffset(selection, getter_AddRefs(parent), &selOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     while (parent && (parent!=root))
     {
       if (nsHTMLEditUtils::IsNodeThatCanOutdent(parent))
@@ -1091,7 +1091,7 @@ nsHTMLEditRules::GetIndentState(PRBool *aCanIndent, PRBool *aCanOutdent)
 
     // test end parent hierarchy
     res = mHTMLEditor->GetEndNodeAndOffset(selection, getter_AddRefs(parent), &selOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     while (parent && (parent!=root))
     {
       if (nsHTMLEditUtils::IsNodeThatCanOutdent(parent))
@@ -1123,7 +1123,7 @@ nsHTMLEditRules::GetParagraphState(PRBool *aMixed, nsAString &outFormat)
   
   nsCOMArray<nsIDOMNode> arrayOfNodes;
   nsresult res = GetParagraphFormatNodes(arrayOfNodes, PR_TRUE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // post process list.  We need to replace any block nodes that are not format
   // nodes with their content.  This is so we only have to look "up" the hierarchy
@@ -1139,7 +1139,7 @@ nsHTMLEditRules::GetParagraphState(PRBool *aMixed, nsAString &outFormat)
     {
       // arrayOfNodes.RemoveObject(curNode);
       res = AppendInnerFormatNodes(arrayOfNodes, curNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   
@@ -1152,9 +1152,9 @@ nsHTMLEditRules::GetParagraphState(PRBool *aMixed, nsAString &outFormat)
     PRInt32 selOffset;
     nsCOMPtr<nsISelection>selection;
     res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = mHTMLEditor->GetStartNodeAndOffset(selection, getter_AddRefs(selNode), &selOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!selNode) return NS_ERROR_NULL_POINTER;
     arrayOfNodes.AppendObject(selNode);
     listCount = 1;
@@ -1282,7 +1282,7 @@ nsresult
 nsHTMLEditRules::WillInsert(nsISelection *aSelection, PRBool *aCancel)
 {
   nsresult res = nsTextEditRules::WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res; 
+  NS_ENSURE_SUCCESS(res, res); 
   
   // Adjust selection to prevent insertion after a moz-BR.
   // this next only works for collapsed selections right now,
@@ -1290,7 +1290,7 @@ nsHTMLEditRules::WillInsert(nsISelection *aSelection, PRBool *aCancel)
   // (no good way to extend start or end of selection)
   PRBool bCollapsed;
   res = aSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!bCollapsed) return NS_OK;
 
   // if we are after a mozBR in the same block, then move selection
@@ -1300,7 +1300,7 @@ nsHTMLEditRules::WillInsert(nsISelection *aSelection, PRBool *aCancel)
   // get the (collapsed) selection location
   res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(selNode),
                                            &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // get prior node
   res = mHTMLEditor->GetPriorHTMLNode(selNode, selOffset,
                                       address_of(priorNode));
@@ -1317,16 +1317,16 @@ nsHTMLEditRules::WillInsert(nsISelection *aSelection, PRBool *aCancel)
       // that is in the same block as the selection.  We need to move
       // the selection start to be before the mozBR.
       res = nsEditor::GetNodeLocation(priorNode, address_of(selNode), &selOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = aSelection->Collapse(selNode,selOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
 
   // we need to get the doc
   nsCOMPtr<nsIDOMDocument>doc;
   res = mHTMLEditor->GetDocument(getter_AddRefs(doc));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!doc) return NS_ERROR_NULL_POINTER;
     
   // for every property that is set, insert a new inline style node
@@ -1376,22 +1376,22 @@ nsHTMLEditRules::WillInsertText(PRInt32          aAction,
   // if the selection isn't collapsed, delete it.
   PRBool bCollapsed;
   res = aSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!bCollapsed)
   {
     res = mHTMLEditor->DeleteSelection(nsIEditor::eNone);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   res = WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // initialize out param
   // we want to ignore result of WillInsert()
   *aCancel = PR_FALSE;
   
   // get the (collapsed) selection location
   res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // dont put text in places that can't have it
   if (!mHTMLEditor->IsTextNode(selNode) &&
@@ -1401,7 +1401,7 @@ nsHTMLEditRules::WillInsertText(PRInt32          aAction,
   // we need to get the doc
   nsCOMPtr<nsIDOMDocument>doc;
   res = mHTMLEditor->GetDocument(getter_AddRefs(doc));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!doc) return NS_ERROR_NULL_POINTER;
     
   if (aAction == kInsertTextIME) 
@@ -1417,7 +1417,7 @@ nsHTMLEditRules::WillInsertText(PRInt32          aAction,
       nsWSRunObject wsObj(mHTMLEditor, selNode, selOffset);
       res = wsObj.InsertText(*inString, address_of(selNode), &selOffset, doc);
     }
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   else // aAction == kInsertText
   {
@@ -1429,7 +1429,7 @@ nsHTMLEditRules::WillInsertText(PRInt32          aAction,
     // We remember this so that we know how to handle tabs.
     PRBool isPRE;
     res = mHTMLEditor->IsPreformatted(selNode, &isPRE);
-    if (NS_FAILED(res)) return res;    
+    NS_ENSURE_SUCCESS(res, res);    
     
     // turn off the edit listener: we know how to
     // build the "doc changed range" ourselves, and it's
@@ -1481,7 +1481,7 @@ nsHTMLEditRules::WillInsertText(PRInt32          aAction,
         {
           res = mHTMLEditor->InsertTextImpl(subStr, address_of(curNode), &curOffset, doc);
         }
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     else
@@ -1515,22 +1515,22 @@ nsHTMLEditRules::WillInsertText(PRInt32          aAction,
         if (subStr.Equals(tabStr))
         {
           res = wsObj.InsertText(spacesStr, address_of(curNode), &curOffset, doc);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           pos++;
         }
         // is it a return?
         else if (subStr.Equals(newlineStr))
         {
           res = wsObj.InsertBreak(address_of(curNode), &curOffset, address_of(unused), nsIEditor::eNone);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           pos++;
         }
         else
         {
           res = wsObj.InsertText(subStr, address_of(curNode), &curOffset, doc);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     nsCOMPtr<nsISelection> selection(aSelection);
@@ -1545,12 +1545,12 @@ nsHTMLEditRules::WillInsertText(PRInt32          aAction,
       if (!mDocChangeRange) return NS_ERROR_NULL_POINTER;
     }
     res = mDocChangeRange->SetStart(selNode, selOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (curNode)
       res = mDocChangeRange->SetEnd(curNode, curOffset);
     else
       res = mDocChangeRange->SetEnd(selNode, selOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return res;
 }
@@ -1585,15 +1585,15 @@ nsHTMLEditRules::WillInsertBreak(nsISelection *aSelection, PRBool *aCancel, PRBo
   // if the selection isn't collapsed, delete it.
   PRBool bCollapsed;
   nsresult res = aSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!bCollapsed)
   {
     res = mHTMLEditor->DeleteSelection(nsIEditor::eNone);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   res = WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // initialize out param
   // we want to ignore result of WillInsert()
@@ -1604,7 +1604,7 @@ nsHTMLEditRules::WillInsertBreak(nsISelection *aSelection, PRBool *aCancel, PRBo
   if (IsMailEditor())
   {
     res = SplitMailCites(aSelection, IsPlaintextEditor(), aHandled);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (*aHandled) return NS_OK;
   }
 
@@ -1613,7 +1613,7 @@ nsHTMLEditRules::WillInsertBreak(nsISelection *aSelection, PRBool *aCancel, PRBo
   PRInt32 offset;
   
   res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(node), &offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!node) return NS_ERROR_FAILURE;
     
   // identify the block
@@ -1644,10 +1644,10 @@ nsHTMLEditRules::WillInsertBreak(nsISelection *aSelection, PRBool *aCancel, PRBo
   {
     PRUint32 blockLen;
     res = mHTMLEditor->GetLengthOfDOMNode(blockParent, blockLen);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     nsCOMPtr<nsIDOMNode> brNode;
     res = mHTMLEditor->CreateBR(blockParent, blockLen, address_of(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   nsCOMPtr<nsIDOMNode> listItem = IsInListItem(blockParent);
@@ -1670,7 +1670,7 @@ nsHTMLEditRules::WillInsertBreak(nsISelection *aSelection, PRBool *aCancel, PRBo
   else if (nsHTMLEditUtils::IsParagraph(blockParent))
   {
     res = ReturnInParagraph(aSelection, blockParent, node, offset, aCancel, aHandled);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // fall through, we may not have handled it in ReturnInParagraph()
   }
   
@@ -1704,11 +1704,11 @@ nsHTMLEditRules::StandardBreakImpl(nsIDOMNode *aNode, PRInt32 aOffset, nsISelect
     PRInt32 visOffset=0, newOffset;
     PRInt16 wsType;
     res = wsObj.PriorVisibleNode(node, aOffset, address_of(visNode), &visOffset, &wsType);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (wsType & nsWSRunObject::eBlock)
       bAfterBlock = PR_TRUE;
     res = wsObj.NextVisibleNode(node, aOffset, address_of(visNode), &visOffset, &wsType);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (wsType & nsWSRunObject::eBlock)
       bBeforeBlock = PR_TRUE;
     if (mHTMLEditor->IsInLink(node, address_of(linkNode)))
@@ -1716,18 +1716,18 @@ nsHTMLEditRules::StandardBreakImpl(nsIDOMNode *aNode, PRInt32 aOffset, nsISelect
       // split the link
       nsCOMPtr<nsIDOMNode> linkParent;
       res = linkNode->GetParentNode(getter_AddRefs(linkParent));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->SplitNodeDeep(linkNode, node, aOffset, &newOffset, PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // reset {node,aOffset} to the point where link was split
       node = linkParent;
       aOffset = newOffset;
     }
     res = wsObj.InsertBreak(address_of(node), &aOffset, address_of(brNode), nsIEditor::eNone);
   }
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = nsEditor::GetNodeLocation(brNode, address_of(node), &aOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (bAfterBlock && bBeforeBlock)
   {
     // we just placed a br between block boundaries.  
@@ -1744,7 +1744,7 @@ nsHTMLEditRules::StandardBreakImpl(nsIDOMNode *aNode, PRInt32 aOffset, nsISelect
      PRInt32 visOffset=0;
      PRInt16 wsType;
      res = wsObj.NextVisibleNode(node, aOffset+1, address_of(secondBR), &visOffset, &wsType);
-     if (NS_FAILED(res)) return res;
+     NS_ENSURE_SUCCESS(res, res);
      if (wsType==nsWSRunObject::eBreak)
      {
        // the next thing after the break we inserted is another break.  Move the 2nd 
@@ -1755,11 +1755,11 @@ nsHTMLEditRules::StandardBreakImpl(nsIDOMNode *aNode, PRInt32 aOffset, nsISelect
        nsCOMPtr<nsIDOMNode> brParent;
        PRInt32 brOffset;
        res = nsEditor::GetNodeLocation(secondBR, address_of(brParent), &brOffset);
-       if (NS_FAILED(res)) return res;
+       NS_ENSURE_SUCCESS(res, res);
        if ((brParent != node) || (brOffset != (aOffset+1)))
        {
          res = mHTMLEditor->MoveNode(secondBR, node, aOffset+1);
-         if (NS_FAILED(res)) return res;
+         NS_ENSURE_SUCCESS(res, res);
        }
      }
     // SetInterlinePosition(PR_TRUE) means we want the caret to stick to the content on the "right".
@@ -1796,9 +1796,9 @@ nsHTMLEditRules::SplitMailCites(nsISelection *aSelection, PRBool aPlaintext, PRB
   nsCOMPtr<nsIDOMNode> citeNode, selNode, leftCite, rightCite;
   PRInt32 selOffset, newOffset;
   nsresult res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = GetTopEnclosingMailCite(selNode, address_of(citeNode), aPlaintext);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (citeNode)
   {
     // If our selection is just before a break, nudge it to be
@@ -1814,7 +1814,7 @@ nsHTMLEditRules::SplitMailCites(nsISelection *aSelection, PRBool aPlaintext, PRB
     PRInt32 visOffset=0;
     PRInt16 wsType;
     res = wsObj.NextVisibleNode(selNode, selOffset, address_of(visNode), &visOffset, &wsType);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (wsType==nsWSRunObject::eBreak)
     {
       // ok, we are just before a break.  is it inside the mailquote?
@@ -1823,7 +1823,7 @@ nsHTMLEditRules::SplitMailCites(nsISelection *aSelection, PRBool aPlaintext, PRB
       {
         // it is.  so lets reset our selection to be just after it.
         res = mHTMLEditor->GetNodeLocation(visNode, address_of(selNode), &selOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         ++selOffset;
       }
     }
@@ -1831,15 +1831,15 @@ nsHTMLEditRules::SplitMailCites(nsISelection *aSelection, PRBool aPlaintext, PRB
     nsCOMPtr<nsIDOMNode> brNode;
     res = mHTMLEditor->SplitNodeDeep(citeNode, selNode, selOffset, &newOffset, 
                        PR_TRUE, address_of(leftCite), address_of(rightCite));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = citeNode->GetParentNode(getter_AddRefs(selNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = mHTMLEditor->CreateBR(selNode, newOffset, address_of(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // want selection before the break, and on same line
     selPriv->SetInterlinePosition(PR_TRUE);
     res = aSelection->Collapse(selNode, newOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // if citeNode wasn't a block, we might also want another break before it.
     // We need to examine the content both before the br we just added and also
     // just after it.  If we don't have another br or block boundary adjacent,
@@ -1851,20 +1851,20 @@ nsHTMLEditRules::SplitMailCites(nsISelection *aSelection, PRBool aPlaintext, PRB
       PRInt32 visOffset=0;
       PRInt16 wsType;
       res = wsObj.PriorVisibleNode(selNode, newOffset, address_of(visNode), &visOffset, &wsType);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if ((wsType==nsWSRunObject::eNormalWS) || 
           (wsType==nsWSRunObject::eText)     ||
           (wsType==nsWSRunObject::eSpecial))
       {
         nsWSRunObject wsObjAfterBR(mHTMLEditor, selNode, newOffset+1);
         res = wsObjAfterBR.NextVisibleNode(selNode, newOffset+1, address_of(visNode), &visOffset, &wsType);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if ((wsType==nsWSRunObject::eNormalWS) || 
             (wsType==nsWSRunObject::eText)     ||
             (wsType==nsWSRunObject::eSpecial))
         {
           res = mHTMLEditor->CreateBR(selNode, newOffset, address_of(brNode));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
       }
     }
@@ -1875,14 +1875,14 @@ nsHTMLEditRules::SplitMailCites(nsISelection *aSelection, PRBool aPlaintext, PRB
       res = mHTMLEditor->IsEmptyNode(leftCite, &bEmptyCite, PR_TRUE, PR_FALSE);
       if (NS_SUCCEEDED(res) && bEmptyCite)
         res = mHTMLEditor->DeleteNode(leftCite);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     if (rightCite)
     {
       res = mHTMLEditor->IsEmptyNode(rightCite, &bEmptyCite, PR_TRUE, PR_FALSE);
       if (NS_SUCCEEDED(res) && bEmptyCite)
         res = mHTMLEditor->DeleteNode(rightCite);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     *aHandled = PR_TRUE;
   }
@@ -1915,7 +1915,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
   nsresult res = NS_OK;
   PRBool bCollapsed, join = PR_FALSE;
   res = aSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // origCollapsed is used later to determine whether we should join 
   // blocks. We don't really care about bCollapsed because it will be 
@@ -1941,7 +1941,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
   }
   
   res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(startNode), &startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!startNode) return NS_ERROR_FAILURE;
     
   // get the root element  
@@ -1952,12 +1952,12 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
   {
     // if we are inside an empty block, delete it.
     res = CheckForEmptyBlock(startNode, rootNode, aSelection, aHandled);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (*aHandled) return NS_OK;
         
     // Test for distance between caret and text that will be deleted
     res = CheckBidiLevelForDeletion(aSelection, startNode, startOffset, aAction, aCancel);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (*aCancel) return NS_OK;
 
     res = mHTMLEditor->ExtendSelectionForDelete(aSelection, &aAction);
@@ -1969,11 +1969,11 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
 
     // ExtendSelectionForDelete() may have changed the selection, update it
     res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(startNode), &startOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!startNode) return NS_ERROR_FAILURE;
     
     res = aSelection->GetIsCollapsed(&bCollapsed);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   if (bCollapsed)
@@ -1989,7 +1989,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
       res = wsObj.NextVisibleNode(startNode, startOffset, address_of(visNode), &visOffset, &wsType);
     else
       res = wsObj.PriorVisibleNode(startNode, startOffset, address_of(visNode), &visOffset, &wsType);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     if (!visNode) // can't find anything to delete!
     {
@@ -2005,7 +2005,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
       else
         res = wsObj.DeleteWSBackward();
       *aHandled = PR_TRUE;
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = InsertBRIfNeeded(aSelection);
       return res;
     } 
@@ -2044,11 +2044,11 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
         NS_ENSURE_SUCCESS(res, res);
       }
       res = nsWSRunObject::PrepareToDeleteRange(mHTMLEditor, address_of(visNode), &so, address_of(visNode), &eo);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       nsCOMPtr<nsIDOMCharacterData> nodeAsText(do_QueryInterface(visNode));
       res = mHTMLEditor->DeleteText(nodeAsText, NS_MIN(so, eo), PR_ABS(eo - so));
       *aHandled = PR_TRUE;
-      if (NS_FAILED(res)) return res;    
+      NS_ENSURE_SUCCESS(res, res);    
       res = InsertBRIfNeeded(aSelection);
       return res;
     }
@@ -2060,7 +2060,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
       if (nsTextEditUtils::IsBreak(visNode) && !mHTMLEditor->IsVisBreak(visNode))
       {
         res = mHTMLEditor->DeleteNode(visNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         return WillDeleteSelection(aSelection, aAction, aCancel, aHandled);
       }
       
@@ -2091,12 +2091,12 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
         PRBool moveOnly = PR_TRUE;
 
         res = nsEditor::GetNodeLocation(visNode, address_of(selNode), &selOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
 
         PRBool interLineIsRight;
         nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(aSelection));
         res = selPriv->GetInterlinePosition(&interLineIsRight);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
 
         if (startNode == selNode &&
             startOffset -1 == selOffset &&
@@ -2123,16 +2123,16 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
           PRInt32 otherOffset;
 
           res = wsObj.NextVisibleNode(startNode, startOffset, address_of(otherNode), &otherOffset, &otherWSType);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
 
           if (otherWSType == nsWSRunObject::eBreak)
           {
             // Delete the <br>
 
             res = nsWSRunObject::PrepareToDeleteNode(mHTMLEditor, otherNode);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
             res = mHTMLEditor->DeleteNode(otherNode);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
 
           return NS_OK;
@@ -2142,13 +2142,13 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
 
       // found break or image, or hr.  
       res = nsWSRunObject::PrepareToDeleteNode(mHTMLEditor, visNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // remember sibling to visnode, if any
       nsCOMPtr<nsIDOMNode> sibling, stepbrother;
       mHTMLEditor->GetPriorHTMLSibling(visNode, address_of(sibling));
       // delete the node, and join like nodes if appropriate
       res = mHTMLEditor->DeleteNode(visNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // we did something, so lets say so.
       *aHandled = PR_TRUE;
       // is there a prior node and are they siblings?
@@ -2161,12 +2161,12 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
         {
           // if so, join them!
           res = JoinNodesSmart(sibling, startNode, address_of(selNode), &selOffset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           // fix up selection
           res = aSelection->Collapse(selNode, selOffset);
         }
       }
-      if (NS_FAILED(res)) return res;    
+      NS_ENSURE_SUCCESS(res, res);    
       res = InsertBRIfNeeded(aSelection);
       return res;
     }
@@ -2193,21 +2193,21 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
         res = wsObj.PriorVisibleNode(startNode, startOffset, address_of(otherNode), &otherOffset, &otherWSType);
       else
         res = wsObj.NextVisibleNode(startNode, startOffset, address_of(otherNode), &otherOffset, &otherWSType);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       
       // first find the adjacent node in the block
       nsCOMPtr<nsIDOMNode> leafNode, leftNode, rightNode, leftParent, rightParent;
       if (aAction == nsIEditor::ePrevious) 
       {
         res = mHTMLEditor->GetLastEditableLeaf( visNode, address_of(leafNode));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         leftNode = leafNode;
         rightNode = startNode;
       }
       else
       {
         res = mHTMLEditor->GetFirstEditableLeaf( visNode, address_of(leafNode));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         leftNode = startNode;
         rightNode = leafNode;
       }
@@ -2215,7 +2215,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
       if (nsTextEditUtils::IsBreak(otherNode))
       {
         res = mHTMLEditor->DeleteNode(otherNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         *aHandled = PR_TRUE;
         bDeletedBR = PR_TRUE;
       }
@@ -2234,7 +2234,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
         nsCOMPtr<nsIDOMNode> newSelNode;
         PRInt32 newSelOffset;
         res = GetGoodSelPointForNode(leafNode, aAction, address_of(newSelNode), &newSelOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         aSelection->Collapse(newSelNode, newSelOffset);
         return res;
       }
@@ -2285,13 +2285,13 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
       if (aAction == nsIEditor::ePrevious) 
       {
         res = mHTMLEditor->GetPriorHTMLNode(visNode, address_of(leftNode));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         rightNode = startNode;
       }
       else
       {
         res = mHTMLEditor->GetNextHTMLNode( visNode, address_of(rightNode));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         leftNode = startNode;
       }
 
@@ -2340,19 +2340,19 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
   // else we have a non collapsed selection
   // first adjust the selection
   res = ExpandSelectionForDeletion(aSelection);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // remember that we did a ranged delete for the benefit of AfterEditInner().
   mDidRangedDelete = PR_TRUE;
   
   // refresh start and end points
   res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(startNode), &startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!startNode) return NS_ERROR_FAILURE;
   nsCOMPtr<nsIDOMNode> endNode;
   PRInt32 endOffset;
   res = mHTMLEditor->GetEndNodeAndOffset(aSelection, getter_AddRefs(endNode), &endOffset);
-  if (NS_FAILED(res)) return res; 
+  NS_ENSURE_SUCCESS(res, res); 
   if (!endNode) return NS_ERROR_FAILURE;
 
   // figure out if the endpoints are in nodes that can be merged  
@@ -2363,7 +2363,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
     res = nsWSRunObject::PrepareToDeleteRange(mHTMLEditor,
                                             address_of(startNode), &startOffset, 
                                             address_of(endNode), &endOffset);
-    if (NS_FAILED(res)) return res; 
+    NS_ENSURE_SUCCESS(res, res); 
   }
   
   {
@@ -2375,7 +2375,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
     if (endNode == startNode)
     {
       res = mHTMLEditor->DeleteSelectionImpl(aAction);
-      if (NS_FAILED(res)) return res; 
+      NS_ENSURE_SUCCESS(res, res); 
     }
     else
     {
@@ -2383,10 +2383,10 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
       nsCOMPtr<nsIDOMNode> endCiteNode, startCiteNode;
       res = GetTopEnclosingMailCite(startNode, address_of(startCiteNode), 
                                     IsPlaintextEditor());
-      if (NS_FAILED(res)) return res; 
+      NS_ENSURE_SUCCESS(res, res); 
       res = GetTopEnclosingMailCite(endNode, address_of(endCiteNode), 
                                     IsPlaintextEditor());
-      if (NS_FAILED(res)) return res; 
+      NS_ENSURE_SUCCESS(res, res); 
       
       // if we only have a mailcite at one of the two endpoints, set the directionality
       // of the deletion so that the selection will end up outside the mailcite.
@@ -2436,10 +2436,10 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
           {
             // first delete the selection
             res = mHTMLEditor->DeleteSelectionImpl(aAction);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
             // then join para's, insert break
             res = mHTMLEditor->JoinNodeDeep(leftParent,rightParent,address_of(selNode),&selOffset);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
             // fix up selection
             res = aSelection->Collapse(selNode,selOffset);
             return res;
@@ -2449,10 +2449,10 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
           {
             // first delete the selection
             res = mHTMLEditor->DeleteSelectionImpl(aAction);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
             // join blocks
             res = mHTMLEditor->JoinNodeDeep(leftParent,rightParent,address_of(selNode),&selOffset);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
             // fix up selection
             res = aSelection->Collapse(selNode,selOffset);
             return res;
@@ -2464,7 +2464,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
         nsCOMPtr<nsIEnumerator> enumerator;
         nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(aSelection));
         res = selPriv->GetEnumerator(getter_AddRefs(enumerator));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (!enumerator) return NS_ERROR_UNEXPECTED;
 
         join = PR_TRUE;
@@ -2473,7 +2473,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
         {
           nsCOMPtr<nsISupports> currentItem;
           res = enumerator->CurrentItem(getter_AddRefs(currentItem));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           if (!currentItem) return NS_ERROR_UNEXPECTED;
 
           // build a list of nodes in the range
@@ -2482,9 +2482,9 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
           nsTrivialFunctor functor;
           nsDOMSubtreeIterator iter;
           res = iter.Init(range);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = iter.AppendList(functor, arrayOfNodes);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
       
           // now that we have the list, delete non table elements
           PRInt32 listCount = arrayOfNodes.Count();
@@ -2524,7 +2524,7 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
           if (len > (PRUint32)startOffset)
           {
             res = mHTMLEditor->DeleteText(nodeAsText,startOffset,len-startOffset);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
         }
         if ( mHTMLEditor->IsTextNode(endNode) )
@@ -2535,14 +2535,14 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection,
           if (endOffset)
           {
             res = mHTMLEditor->DeleteText(nodeAsText,0,endOffset);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
         }
 
         if (join) {
           res = JoinBlocks(address_of(leftParent), address_of(rightParent),
                            aCancel);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
       }
     }
@@ -2582,7 +2582,7 @@ nsHTMLEditRules::InsertBRIfNeeded(nsISelection *aSelection)
   nsCOMPtr<nsIDOMNode> node;
   PRInt32 offset;
   nsresult res = mEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(node), &offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!node) return NS_ERROR_FAILURE;
 
   // examine selection
@@ -2629,13 +2629,13 @@ nsHTMLEditRules::GetGoodSelPointForNode(nsIDOMNode *aNode, nsIEditor::EDirection
       PRUint32 len;
       res = mHTMLEditor->GetLengthOfDOMNode(aNode, len);
       *outSelOffset = PRInt32(len);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   else 
   {
     res = nsEditor::GetNodeLocation(aNode, outSelNode, outSelOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!nsTextEditUtils::IsBreak(aNode) || mHTMLEditor->IsVisBreak(aNode))
     {
       if (aAction == nsIEditor::ePrevious)
@@ -2739,13 +2739,13 @@ nsHTMLEditRules::JoinBlocks(nsCOMPtr<nsIDOMNode> *aLeftBlock,
     // Do ws adjustment.  This just destroys non-visible ws at boundaries we will be joining.
     rightOffset++;
     res = nsWSRunObject::ScrubBlockBoundary(mHTMLEditor, aLeftBlock, nsWSRunObject::kBlockEnd);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = nsWSRunObject::ScrubBlockBoundary(mHTMLEditor, aRightBlock, nsWSRunObject::kAfterBlock, &rightOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // Do br adjustment.
     nsCOMPtr<nsIDOMNode> brNode;
     res = CheckForInvisibleBR(*aLeftBlock, kBlockEnd, address_of(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (bMergeLists)
     {
       // idea here is to take all children in  rightList that are past
@@ -2779,13 +2779,13 @@ nsHTMLEditRules::JoinBlocks(nsCOMPtr<nsIDOMNode> *aLeftBlock,
     // tricky case.  right block is inside left block.
     // Do ws adjustment.  This just destroys non-visible ws at boundaries we will be joining.
     res = nsWSRunObject::ScrubBlockBoundary(mHTMLEditor, aRightBlock, nsWSRunObject::kBlockStart);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = nsWSRunObject::ScrubBlockBoundary(mHTMLEditor, aLeftBlock, nsWSRunObject::kBeforeBlock, &leftOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // Do br adjustment.
     nsCOMPtr<nsIDOMNode> brNode;
     res = CheckForInvisibleBR(*aLeftBlock, kBeforeBlock, address_of(brNode), leftOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (bMergeLists)
     {
       res = MoveContents(rightList, leftList, &leftOffset);
@@ -2805,11 +2805,11 @@ nsHTMLEditRules::JoinBlocks(nsCOMPtr<nsIDOMNode> *aLeftBlock,
     
     // adjust whitespace at block boundaries
     res = nsWSRunObject::PrepareToJoinBlocks(mHTMLEditor, *aLeftBlock, *aRightBlock);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // Do br adjustment.
     nsCOMPtr<nsIDOMNode> brNode;
     res = CheckForInvisibleBR(*aLeftBlock, kBlockEnd, address_of(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (bMergeLists || mHTMLEditor->NodesSameType(*aLeftBlock, *aRightBlock))
     {
       // nodes are same type.  merge them.
@@ -2852,7 +2852,7 @@ nsHTMLEditRules::MoveBlock(nsIDOMNode *aLeftBlock, nsIDOMNode *aRightBlock, PRIn
   nsCOMPtr<nsISupports> isupports;
   // GetNodesFromPoint is the workhorse that figures out what we wnat to move.
   nsresult res = GetNodesFromPoint(DOMPoint(aRightBlock,aRightOffset), kMakeList, arrayOfNodes, PR_TRUE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   PRInt32 listCount = arrayOfNodes.Count();
   PRInt32 i;
   for (i=0; i<listCount; i++)
@@ -2863,7 +2863,7 @@ nsHTMLEditRules::MoveBlock(nsIDOMNode *aLeftBlock, nsIDOMNode *aRightBlock, PRIn
     {
       // For block nodes, move their contents only, then delete block.
       res = MoveContents(curNode, aLeftBlock, &aLeftOffset); 
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->DeleteNode(curNode);
     }
     else
@@ -2891,23 +2891,23 @@ nsHTMLEditRules::MoveNodeSmart(nsIDOMNode *aSource, nsIDOMNode *aDest, PRInt32 *
   nsAutoString tag;
   nsresult res;
   res = mHTMLEditor->GetTagString(aSource, tag);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   ToLowerCase(tag);
   // check if this node can go into the destination node
   if (mHTMLEditor->CanContainTag(aDest, tag))
   {
     // if it can, move it there
     res = mHTMLEditor->MoveNode(aSource, aDest, *aOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (*aOffset != -1) ++(*aOffset);
   }
   else
   {
     // if it can't, move it's children, and then delete it.
     res = MoveContents(aSource, aDest, aOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = mHTMLEditor->DeleteNode(aSource);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return NS_OK;
 }
@@ -2934,7 +2934,7 @@ nsHTMLEditRules::MoveContents(nsIDOMNode *aSource, nsIDOMNode *aDest, PRInt32 *a
   while (child)
   {
     res = MoveNodeSmart(child, aDest, aOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     aSource->GetFirstChild(getter_AddRefs(child));
   }
   return NS_OK;
@@ -2961,7 +2961,7 @@ nsHTMLEditRules::DeleteNonTableElements(nsIDOMNode *aNode)
         nsCOMPtr<nsIDOMNode> node;
         children->Item(j,getter_AddRefs(node));
         res = DeleteNonTableElements(node);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
 
       }
     }
@@ -2969,7 +2969,7 @@ nsHTMLEditRules::DeleteNonTableElements(nsIDOMNode *aNode)
   else
   {
     res = mHTMLEditor->DeleteNode(aNode);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return res;
 }
@@ -2985,14 +2985,14 @@ nsHTMLEditRules::DidDeleteSelection(nsISelection *aSelection,
   nsCOMPtr<nsIDOMNode> startNode;
   PRInt32 startOffset;
   nsresult res = mEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(startNode), &startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!startNode) return NS_ERROR_FAILURE;
   
   // find any enclosing mailcite
   nsCOMPtr<nsIDOMNode> citeNode;
   res = GetTopEnclosingMailCite(startNode, address_of(citeNode), 
                                 IsPlaintextEditor());
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (citeNode)
   {
     PRBool isEmpty = PR_TRUE, seenBR = PR_FALSE;
@@ -3003,11 +3003,11 @@ nsHTMLEditRules::DidDeleteSelection(nsISelection *aSelection,
       PRInt32 offset;
       nsEditor::GetNodeLocation(citeNode, address_of(parent), &offset);
       res = mHTMLEditor->DeleteNode(citeNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (parent && seenBR)
       {
         res = mHTMLEditor->CreateBR(parent, offset, address_of(brNode));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         aSelection->Collapse(parent, offset);
       }
     }
@@ -3029,7 +3029,7 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
   if (!aSelection || !aListType || !aCancel || !aHandled) { return NS_ERROR_NULL_POINTER; }
 
   nsresult res = WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // initialize out param
   // we want to ignore result of WillInsert()
@@ -3053,12 +3053,12 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
   *aHandled = PR_TRUE;
 
   res = NormalizeSelection(aSelection);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsAutoSelectionReset selectionResetter(aSelection, mHTMLEditor);
   
   nsCOMArray<nsIDOMNode> arrayOfNodes;
   res = GetListActionNodes(arrayOfNodes, aEntireList);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   PRInt32 listCount = arrayOfNodes.Count();
   
@@ -3088,21 +3088,21 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
       for (j=0; j<(PRInt32)listCount; j++)
       {
         res = mHTMLEditor->DeleteNode(arrayOfNodes[j]);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     
     // get selection location
     res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     // make sure we can put a list here
     res = SplitAsNeeded(aListType, address_of(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = mHTMLEditor->CreateNode(*aListType, parent, offset, getter_AddRefs(theList));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = mHTMLEditor->CreateNode(itemType, theList, 0, getter_AddRefs(theListItem));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // remember our new block for postprocessing
     mNewBlock = theListItem;
     // put selection in new list item
@@ -3116,7 +3116,7 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
   // then look inside of it until we find inner list or content.
 
   res = LookInsideDivBQandList(arrayOfNodes);
-  if (NS_FAILED(res)) return res;                                 
+  NS_ENSURE_SUCCESS(res, res);                                 
 
   // Ok, now go through all the nodes and put then in the list, 
   // or whatever is approriate.  Wohoo!
@@ -3134,7 +3134,7 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
     nsCOMPtr<nsIDOMNode> curNode = arrayOfNodes[i];
     PRInt32 offset;
     res = nsEditor::GetNodeLocation(curNode, address_of(curParent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   
     // make sure we don't assemble content that is in different table cells into the same list.
     // respect table cell boundaries when listifying.
@@ -3142,7 +3142,7 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
     {
       PRBool bInDifTblElems;
       res = InDifferentTableElements(curList, curNode, &bInDifTblElems);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (bInDifTblElems)
         curList = nsnull;
     }
@@ -3151,7 +3151,7 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
     if (nsTextEditUtils::IsBreak(curNode)) 
     {
       res = mHTMLEditor->DeleteNode(curNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       prevListItem = 0;
       continue;
     }
@@ -3159,7 +3159,7 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
     else if (IsEmptyInline(curNode)) 
     {
       res = mHTMLEditor->DeleteNode(curNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       continue;
     }
     
@@ -3177,17 +3177,17 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
         // ConvertListType first: that routine
         // handles converting the list item types, if needed
         res = mHTMLEditor->MoveNode(curNode, curList, -1);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = ConvertListType(curNode, address_of(newBlock), *aListType, itemType);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = mHTMLEditor->RemoveBlockContainer(newBlock);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       else
       {
         // replace list with new list type
         res = ConvertListType(curNode, address_of(newBlock), *aListType, itemType);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         curList = newBlock;
       }
       prevListItem = 0;
@@ -3207,22 +3207,22 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
         if (!curList || nsEditorUtils::IsDescendantOf(curNode, curList))
         {
           res = mHTMLEditor->SplitNode(curParent, offset, getter_AddRefs(newBlock));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           nsCOMPtr<nsIDOMNode> p;
           PRInt32 o;
           res = nsEditor::GetNodeLocation(curParent, address_of(p), &o);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = mHTMLEditor->CreateNode(*aListType, p, o, getter_AddRefs(curList));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         // move list item to new list
         res = mHTMLEditor->MoveNode(curNode, curList, -1);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // convert list item type if needed
         if (!mHTMLEditor->NodeIsTypeString(curNode,itemType))
         {
           res = mHTMLEditor->ReplaceContainer(curNode, address_of(newBlock), itemType);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
       }
       else
@@ -3237,13 +3237,13 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
           {
             // move list item to new list
             res = mHTMLEditor->MoveNode(curNode, curList, -1);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
         }
         if (!mHTMLEditor->NodeIsTypeString(curNode,itemType))
         {
           res = mHTMLEditor->ReplaceContainer(curNode, address_of(newBlock), itemType);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
       }
       nsCOMPtr<nsIDOMElement> curElement = do_QueryInterface(curNode);
@@ -3254,7 +3254,7 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
       else {
         res = mHTMLEditor->RemoveAttribute(curElement, typestr);
       }
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       continue;
     }
     
@@ -3265,9 +3265,9 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
       prevListItem = nsnull;
       PRInt32 j=i+1;
       res = GetInnerContent(curNode, arrayOfNodes, &j);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->RemoveContainer(curNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       listCount = arrayOfNodes.Count();
       continue;
     }
@@ -3276,9 +3276,9 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
     if (!curList)
     {
       res = SplitAsNeeded(aListType, address_of(curParent), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->CreateNode(*aListType, curParent, offset, getter_AddRefs(curList));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // remember our new block for postprocessing
       mNewBlock = curList;
       // curList is now the correct thing to put curNode in
@@ -3294,7 +3294,7 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
         // this is a continuation of some inline nodes that belong together in
         // the same list item.  use prevListItem
         res = mHTMLEditor->MoveNode(curNode, prevListItem, -1);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       else
       {
@@ -3307,7 +3307,7 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
         {
           res = mHTMLEditor->InsertContainerAbove(curNode, address_of(listItem), itemType);
         }
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (IsInlineNode(curNode)) 
           prevListItem = listItem;
         else
@@ -3323,7 +3323,7 @@ nsHTMLEditRules::WillMakeList(nsISelection *aSelection,
     {
       // tuck the listItem into the end of the active list
       res = mHTMLEditor->MoveNode(listItem, curList, -1);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
 
@@ -3343,17 +3343,17 @@ nsHTMLEditRules::WillRemoveList(nsISelection *aSelection,
   *aHandled = PR_TRUE;
   
   nsresult res = NormalizeSelection(aSelection);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsAutoSelectionReset selectionResetter(aSelection, mHTMLEditor);
   
   nsCOMArray<nsIDOMRange> arrayOfRanges;
   res = GetPromotedRanges(aSelection, arrayOfRanges, kMakeList);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // use these ranges to contruct a list of nodes to act on.
   nsCOMArray<nsIDOMNode> arrayOfNodes;
   res = GetListActionNodes(arrayOfNodes, PR_FALSE);
-  if (NS_FAILED(res)) return res;                                 
+  NS_ENSURE_SUCCESS(res, res);                                 
                                      
   // Remove all non-editable nodes.  Leave them be.
   PRInt32 listCount = arrayOfNodes.Count();
@@ -3378,7 +3378,7 @@ nsHTMLEditRules::WillRemoveList(nsISelection *aSelection,
     nsIDOMNode* curNode = arrayOfNodes[i];
     PRInt32 offset;
     res = nsEditor::GetNodeLocation(curNode, address_of(curParent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     if (nsHTMLEditUtils::IsListItem(curNode))  // unlist this listitem
     {
@@ -3386,13 +3386,13 @@ nsHTMLEditRules::WillRemoveList(nsISelection *aSelection,
       do
       {
         res = PopListItem(curNode, &bOutOfList);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       } while (!bOutOfList); // keep popping it out until it's not in a list anymore
     }
     else if (nsHTMLEditUtils::IsList(curNode)) // node is a list, move list items out
     {
       res = RemoveListStructure(curNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   return res;
@@ -3423,12 +3423,12 @@ nsHTMLEditRules::WillMakeBasicBlock(nsISelection *aSelection,
   *aHandled = PR_FALSE;
   
   nsresult res = WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // initialize out param
   // we want to ignore result of WillInsert()
   *aCancel = PR_FALSE;
   res = NormalizeSelection(aSelection);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsAutoSelectionReset selectionResetter(aSelection, mHTMLEditor);
   nsAutoTxnsConserveSelection dontSpazMySelection(mHTMLEditor);
   *aHandled = PR_TRUE;
@@ -3437,7 +3437,7 @@ nsHTMLEditRules::WillMakeBasicBlock(nsISelection *aSelection,
   // contruct a list of nodes to act on.
   nsCOMArray<nsIDOMNode> arrayOfNodes;
   res = GetNodesFromSelection(aSelection, kMakeBasicBlock, arrayOfNodes);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // Remove all non-editable nodes.  Leave them be.
   PRInt32 listCount = arrayOfNodes.Count();
@@ -3461,7 +3461,7 @@ nsHTMLEditRules::WillMakeBasicBlock(nsISelection *aSelection,
     
     // get selection location
     res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (tString.EqualsLiteral("normal") ||
         tString.IsEmpty() ) // we are removing blocks (going to "body text")
     {
@@ -3477,18 +3477,18 @@ nsHTMLEditRules::WillMakeBasicBlock(nsISelection *aSelection,
         // it gets pushed into a following block after the split, which is visually bad.
         nsCOMPtr<nsIDOMNode> brNode;
         res = mHTMLEditor->GetNextHTMLNode(parent, offset, address_of(brNode));
-        if (NS_FAILED(res)) return res;        
+        NS_ENSURE_SUCCESS(res, res);        
         if (brNode && nsTextEditUtils::IsBreak(brNode))
         {
           res = mHTMLEditor->DeleteNode(brNode);
-          if (NS_FAILED(res)) return res; 
+          NS_ENSURE_SUCCESS(res, res); 
         }
         // do the splits!
         res = mHTMLEditor->SplitNodeDeep(curBlock, parent, offset, &offset, PR_TRUE);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // put a br at the split point
         res = mHTMLEditor->CreateBR(curBlockPar, offset, address_of(brNode));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // put selection at the split point
         res = aSelection->Collapse(curBlockPar, offset);
         selectionResetter.Abort();  // to prevent selection reseter from overriding us.
@@ -3501,19 +3501,19 @@ nsHTMLEditRules::WillMakeBasicBlock(nsISelection *aSelection,
       // consume a br, if needed
       nsCOMPtr<nsIDOMNode> brNode;
       res = mHTMLEditor->GetNextHTMLNode(parent, offset, address_of(brNode), PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (brNode && nsTextEditUtils::IsBreak(brNode))
       {
         res = mHTMLEditor->DeleteNode(brNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // we don't need to act on this node any more
         arrayOfNodes.RemoveObject(brNode);
       }
       // make sure we can put a block here
       res = SplitAsNeeded(aBlockType, address_of(parent), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->CreateNode(*aBlockType, parent, offset, getter_AddRefs(theBlock));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // remember our new block for postprocessing
       mNewBlock = theBlock;
       // delete anything that was in the list of nodes
@@ -3521,9 +3521,9 @@ nsHTMLEditRules::WillMakeBasicBlock(nsISelection *aSelection,
       {
         nsCOMPtr<nsIDOMNode> curNode = arrayOfNodes[0];
         res = mHTMLEditor->DeleteNode(curNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = arrayOfNodes.RemoveObjectAt(0);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       // put selection in new block
       res = aSelection->Collapse(theBlock,0);
@@ -3557,13 +3557,13 @@ nsHTMLEditRules::DidMakeBasicBlock(nsISelection *aSelection,
   // check for empty block.  if so, put a moz br in it.
   PRBool isCollapsed;
   nsresult res = aSelection->GetIsCollapsed(&isCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!isCollapsed) return NS_OK;
 
   nsCOMPtr<nsIDOMNode> parent;
   PRInt32 offset;
   res = nsEditor::GetStartNodeAndOffset(aSelection, getter_AddRefs(parent), &offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = InsertMozBRIfNeeded(parent);
   return res;
 }
@@ -3590,7 +3590,7 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
   if (!aSelection || !aCancel || !aHandled) { return NS_ERROR_NULL_POINTER; }
   
   nsresult res = WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // initialize out param
   // we want to ignore result of WillInsert()
@@ -3598,7 +3598,7 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
   *aHandled = PR_TRUE;
 
   res = NormalizeSelection(aSelection);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsAutoSelectionReset selectionResetter(aSelection, mHTMLEditor);
   nsCOMArray<nsIDOMRange>  arrayOfRanges;
   nsCOMArray<nsIDOMNode> arrayOfNodes;
@@ -3609,13 +3609,13 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
   PRBool bCollapsed;
   nsCOMPtr<nsIDOMNode> liNode;
   res = aSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (bCollapsed) 
   {
     nsCOMPtr<nsIDOMNode> node, block;
     PRInt32 offset;
     nsresult res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(node), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (IsBlockNode(node)) 
       block = node;
     else
@@ -3635,7 +3635,7 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
     // block parent, and then further expands to include any ancestors
     // whose children are all in the range
     res = GetNodesFromSelection(aSelection, kIndent, arrayOfNodes);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   NS_NAMED_LITERAL_STRING(quoteType, "blockquote");
@@ -3647,12 +3647,12 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
     nsAutoString quoteType(NS_LITERAL_STRING("div"));
     // get selection location
     res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // make sure we can put a block here
     res = SplitAsNeeded(&quoteType, address_of(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = mHTMLEditor->CreateNode(quoteType, parent, offset, getter_AddRefs(theBlock));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // remember our new block for postprocessing
     mNewBlock = theBlock;
     RelativeChangeIndentationOfElementNode(theBlock, +1);
@@ -3661,9 +3661,9 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
     {
       nsCOMPtr<nsIDOMNode> curNode = arrayOfNodes[0];
       res = mHTMLEditor->DeleteNode(curNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = arrayOfNodes.RemoveObjectAt(0);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     // put selection in new block
     res = aSelection->Collapse(theBlock,0);
@@ -3690,7 +3690,7 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
 
     PRInt32 offset;
     res = nsEditor::GetNodeLocation(curNode, address_of(curParent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     // some logic for putting list items into nested lists...
     if (nsHTMLEditUtils::IsList(curParent))
@@ -3709,7 +3709,7 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
         if (curListTag == siblingListTag)
         {
           res = mHTMLEditor->MoveNode(curNode, sibling, 0);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           continue;
         }
       }
@@ -3725,7 +3725,7 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
         if (curListTag == siblingListTag)
         {
           res = mHTMLEditor->MoveNode(curNode, sibling, -1);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           continue;
         }
       }
@@ -3743,9 +3743,9 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
         ToLowerCase(listTag);
         // create a new nested list of correct type
         res = SplitAsNeeded(&listTag, address_of(curParent), &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = mHTMLEditor->CreateNode(listTag, curParent, offset, getter_AddRefs(curList));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // curList is now the correct thing to put curNode in
         // remember our new block for postprocessing
         mNewBlock = curList;
@@ -3753,9 +3753,9 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
       // tuck the node into the end of the active list
       PRUint32 listLen;
       res = mHTMLEditor->GetLengthOfDOMNode(curList, listLen);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->MoveNode(curNode, curList, listLen);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     
     else // not a list item
@@ -3769,9 +3769,9 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
         {
           NS_NAMED_LITERAL_STRING(divquoteType, "div");
           res = SplitAsNeeded(&divquoteType, address_of(curParent), &offset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = mHTMLEditor->CreateNode(divquoteType, curParent, offset, getter_AddRefs(curQuote));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           RelativeChangeIndentationOfElementNode(curQuote, +1);
           // remember our new block for postprocessing
           mNewBlock = curQuote;
@@ -3781,9 +3781,9 @@ nsHTMLEditRules::WillCSSIndent(nsISelection *aSelection, PRBool *aCancel, PRBool
         // tuck the node into the end of the active blockquote
         PRUint32 quoteLen;
         res = mHTMLEditor->GetLengthOfDOMNode(curQuote, quoteLen);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = mHTMLEditor->MoveNode(curNode, curQuote, quoteLen);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
   }
@@ -3795,7 +3795,7 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
 {
   if (!aSelection || !aCancel || !aHandled) { return NS_ERROR_NULL_POINTER; }
   nsresult res = WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // initialize out param
   // we want to ignore result of WillInsert()
@@ -3803,7 +3803,7 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
   *aHandled = PR_TRUE;
 
   res = NormalizeSelection(aSelection);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsAutoSelectionReset selectionResetter(aSelection, mHTMLEditor);
   
   // convert the selection ranges into "promoted" selection ranges:
@@ -3813,12 +3813,12 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
   
   nsCOMArray<nsIDOMRange> arrayOfRanges;
   res = GetPromotedRanges(aSelection, arrayOfRanges, kIndent);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // use these ranges to contruct a list of nodes to act on.
   nsCOMArray<nsIDOMNode> arrayOfNodes;
   res = GetNodesForOperation(arrayOfRanges, arrayOfNodes, kIndent);
-  if (NS_FAILED(res)) return res;                                 
+  NS_ENSURE_SUCCESS(res, res);                                 
                                      
   NS_NAMED_LITERAL_STRING(quoteType, "blockquote");
 
@@ -3830,12 +3830,12 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
     
     // get selection location
     res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // make sure we can put a block here
     res = SplitAsNeeded(&quoteType, address_of(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = mHTMLEditor->CreateNode(quoteType, parent, offset, getter_AddRefs(theBlock));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // remember our new block for postprocessing
     mNewBlock = theBlock;
     // delete anything that was in the list of nodes
@@ -3843,9 +3843,9 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
     {
       nsCOMPtr<nsIDOMNode> curNode = arrayOfNodes[0];
       res = mHTMLEditor->DeleteNode(curNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = arrayOfNodes.RemoveObjectAt(0);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     // put selection in new block
     res = aSelection->Collapse(theBlock,0);
@@ -3869,7 +3869,7 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
 
     PRInt32 offset;
     res = nsEditor::GetNodeLocation(curNode, address_of(curParent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
      
     // some logic for putting list items into nested lists...
     if (nsHTMLEditUtils::IsList(curParent))
@@ -3888,7 +3888,7 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
         if (curListTag == siblingListTag)
         {
           res = mHTMLEditor->MoveNode(curNode, sibling, 0);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           continue;
         }
       }
@@ -3905,7 +3905,7 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
         if (curListTag == siblingListTag)
         {
           res = mHTMLEditor->MoveNode(curNode, sibling, -1);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           continue;
         }
       }
@@ -3924,16 +3924,16 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
         ToLowerCase(listTag);
         // create a new nested list of correct type
         res = SplitAsNeeded(&listTag, address_of(curParent), &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = mHTMLEditor->CreateNode(listTag, curParent, offset, getter_AddRefs(curList));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // curList is now the correct thing to put curNode in
         // remember our new block for postprocessing
         mNewBlock = curList;
       }
       // tuck the node into the end of the active list
       res = mHTMLEditor->MoveNode(curNode, curList, -1);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // forget curQuote, if any
       curQuote = nsnull;
     }
@@ -3951,7 +3951,7 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
       {
         if (indentedLI == listitem) continue;  // already indented this list item
         res = nsEditor::GetNodeLocation(listitem, address_of(curParent), &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // check to see if curList is still appropriate.  Which it is if
         // curNode is still right after it in the same list.
         if (curList)
@@ -3967,12 +3967,12 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
           ToLowerCase(listTag);
           // create a new nested list of correct type
           res = SplitAsNeeded(&listTag, address_of(curParent), &offset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = mHTMLEditor->CreateNode(listTag, curParent, offset, getter_AddRefs(curList));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         res = mHTMLEditor->MoveNode(listitem, curList, -1);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // remember we indented this li
         indentedLI = listitem;
       }
@@ -3987,7 +3987,7 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
         {
           PRBool bInDifTblElems;
           res = InDifferentTableElements(curQuote, curNode, &bInDifTblElems);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           if (bInDifTblElems)
             curQuote = nsnull;
         }
@@ -3995,9 +3995,9 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
         if (!curQuote) 
         {
           res = SplitAsNeeded(&quoteType, address_of(curParent), &offset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = mHTMLEditor->CreateNode(quoteType, curParent, offset, getter_AddRefs(curQuote));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           // remember our new block for postprocessing
           mNewBlock = curQuote;
           // curQuote is now the correct thing to put curNode in
@@ -4005,7 +4005,7 @@ nsHTMLEditRules::WillHTMLIndent(nsISelection *aSelection, PRBool *aCancel, PRBoo
           
         // tuck the node into the end of the active blockquote
         res = mHTMLEditor->MoveNode(curNode, curQuote, -1);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // forget curList, if any
         curList = nsnull;
       }
@@ -4028,7 +4028,7 @@ nsHTMLEditRules::WillOutdent(nsISelection *aSelection, PRBool *aCancel, PRBool *
   mHTMLEditor->GetIsCSSEnabled(&useCSS);
 
   res = NormalizeSelection(aSelection);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // some scoping for selection resetting - we may need to tweak it
   {
     nsAutoSelectionReset selectionResetter(aSelection, mHTMLEditor);
@@ -4039,7 +4039,7 @@ nsHTMLEditRules::WillOutdent(nsISelection *aSelection, PRBool *aCancel, PRBool *
     // whose children are all in the range
     nsCOMArray<nsIDOMNode> arrayOfNodes;
     res = GetNodesFromSelection(aSelection, kOutdent, arrayOfNodes);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // Ok, now go through all the nodes and remove a level of blockquoting, 
     // or whatever is appropriate.  Wohoo!
@@ -4055,7 +4055,7 @@ nsHTMLEditRules::WillOutdent(nsISelection *aSelection, PRBool *aCancel, PRBool *
       nsCOMPtr<nsIDOMNode> curNode = arrayOfNodes[i];
       PRInt32 offset;
       res = nsEditor::GetNodeLocation(curNode, address_of(curParent), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       
       // is it a blockquote?
       if (nsHTMLEditUtils::IsBlockquote(curNode)) 
@@ -4068,12 +4068,12 @@ nsHTMLEditRules::WillOutdent(nsISelection *aSelection, PRBool *aCancel, PRBool *
                                    curBlockQuoteIsIndentedWithCSS,
                                    address_of(rememberedLeftBQ),
                                    address_of(rememberedRightBQ));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           curBlockQuote = 0;  firstBQChild = 0;  lastBQChild = 0;
           curBlockQuoteIsIndentedWithCSS = PR_FALSE;
         }
         res = mHTMLEditor->RemoveBlockContainer(curNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         continue;
       }
       // is it a list item?
@@ -4088,13 +4088,13 @@ nsHTMLEditRules::WillOutdent(nsISelection *aSelection, PRBool *aCancel, PRBool *
                                    curBlockQuoteIsIndentedWithCSS,
                                    address_of(rememberedLeftBQ),
                                    address_of(rememberedRightBQ));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           curBlockQuote = 0;  firstBQChild = 0;  lastBQChild = 0;
           curBlockQuoteIsIndentedWithCSS = PR_FALSE;
         }
         PRBool bOutOfList;
         res = PopListItem(curNode, &bOutOfList);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         continue;
       }
       // do we have a blockquote that we are already committed to removing?
@@ -4115,7 +4115,7 @@ nsHTMLEditRules::WillOutdent(nsISelection *aSelection, PRBool *aCancel, PRBool *
                                    curBlockQuoteIsIndentedWithCSS,
                                    address_of(rememberedLeftBQ),
                                    address_of(rememberedRightBQ));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           curBlockQuote = 0;  firstBQChild = 0;  lastBQChild = 0;
           curBlockQuoteIsIndentedWithCSS = PR_FALSE;
           // fall out and handle curNode
@@ -4171,7 +4171,7 @@ nsHTMLEditRules::WillOutdent(nsISelection *aSelection, PRBool *aCancel, PRBool *
           if (nsHTMLEditUtils::IsList(curNode))  // just unwrap this sublist
           {
             res = mHTMLEditor->RemoveBlockContainer(curNode);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
           // handled list item case above
         }
@@ -4185,7 +4185,7 @@ nsHTMLEditRules::WillOutdent(nsISelection *aSelection, PRBool *aCancel, PRBool *
             {
               PRBool bOutOfList;
               res = PopListItem(child, &bOutOfList);
-              if (NS_FAILED(res)) return res;
+              NS_ENSURE_SUCCESS(res, res);
             }
             else if (nsHTMLEditUtils::IsList(child))
             {
@@ -4195,19 +4195,19 @@ nsHTMLEditRules::WillOutdent(nsISelection *aSelection, PRBool *aCancel, PRBool *
               // list of children.
 
               res = mHTMLEditor->MoveNode(child, curParent, offset + 1);
-              if (NS_FAILED(res)) return res;
+              NS_ENSURE_SUCCESS(res, res);
             }
             else
             {
               // delete any non- list items for now
               res = mHTMLEditor->DeleteNode(child);
-              if (NS_FAILED(res)) return res;
+              NS_ENSURE_SUCCESS(res, res);
             }
             curNode->GetLastChild(getter_AddRefs(child));
           }
           // delete the now-empty list
           res = mHTMLEditor->RemoveBlockContainer(curNode);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         else if (useCSS) {
           nsCOMPtr<nsIDOMElement> element;
@@ -4233,7 +4233,7 @@ nsHTMLEditRules::WillOutdent(nsISelection *aSelection, PRBool *aCancel, PRBool *
                                curBlockQuoteIsIndentedWithCSS,
                                address_of(rememberedLeftBQ),
                                address_of(rememberedRightBQ));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   // make sure selection didn't stick to last piece of content in old bq
@@ -4288,7 +4288,7 @@ nsHTMLEditRules::RemovePartOfBlock(nsIDOMNode *aBlock,
   nsresult res = SplitBlock(aBlock, aStartChild, aEndChild,
                             aLeftNode, aRightNode,
                             address_of(middleNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // get rid of part of blockquote we are outdenting
 
   return mHTMLEditor->RemoveBlockContainer(aBlock);
@@ -4311,12 +4311,12 @@ nsHTMLEditRules::SplitBlock(nsIDOMNode *aBlock,
 
   // get split point location
   res = nsEditor::GetNodeLocation(aStartChild, address_of(startParent), &startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // do the splits!
   res = mHTMLEditor->SplitNodeDeep(aBlock, startParent, startOffset, &offset, 
                                    PR_TRUE, address_of(leftNode), address_of(rightNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (rightNode)  aBlock = rightNode;
 
   // remember left portion of block if caller requested
@@ -4325,13 +4325,13 @@ nsHTMLEditRules::SplitBlock(nsIDOMNode *aBlock,
 
   // get split point location
   res = nsEditor::GetNodeLocation(aEndChild, address_of(endParent), &endOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   endOffset++;  // want to be after lastBQChild
 
   // do the splits!
   res = mHTMLEditor->SplitNodeDeep(aBlock, endParent, endOffset, &offset, 
                                    PR_TRUE, address_of(leftNode), address_of(rightNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (leftNode)  aBlock = leftNode;
   
   // remember right portion of block if caller requested
@@ -4357,7 +4357,7 @@ nsHTMLEditRules::OutdentPartOfBlock(nsIDOMNode *aBlock,
                             aLeftNode,
                             aRightNode,
                             address_of(middleNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (aIsBlockIndentedWithCSS)
     res = RelativeChangeIndentationOfElementNode(middleNode, -1);
   else
@@ -4385,13 +4385,13 @@ nsHTMLEditRules::ConvertListType(nsIDOMNode *aList,
     if (nsHTMLEditUtils::IsListItem(child) && !nsEditor::NodeIsTypeString(child, aItemType))
     {
       res = mHTMLEditor->ReplaceContainer(child, address_of(temp), aItemType);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       child = temp;
     }
     else if (nsHTMLEditUtils::IsList(child) && !nsEditor::NodeIsTypeString(child, aListType))
     {
       res = ConvertListType(child, address_of(temp), aListType, aItemType);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       child = temp;
     }
     child->GetNextSibling(getter_AddRefs(temp));
@@ -4632,7 +4632,7 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
   if (!aSelection || !aCancel || !aHandled) { return NS_ERROR_NULL_POINTER; }
 
   nsresult res = WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // initialize out param
   // we want to ignore result of WillInsert()
@@ -4640,7 +4640,7 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
   *aHandled = PR_FALSE;
 
   res = NormalizeSelection(aSelection);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsAutoSelectionReset selectionResetter(aSelection, mHTMLEditor);
 
   // convert the selection ranges into "promoted" selection ranges:
@@ -4650,7 +4650,7 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
   *aHandled = PR_TRUE;
   nsCOMArray<nsIDOMNode> arrayOfNodes;
   res = GetNodesFromSelection(aSelection, kAlign, arrayOfNodes);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // if we don't have any nodes, or we have only a single br, then we are
   // creating an empty alignment div.  We have to do some different things for these.
@@ -4669,7 +4669,7 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
       // all the work is done in AlignBlock
       nsCOMPtr<nsIDOMElement> theElem = do_QueryInterface(theNode);
       res = AlignBlock(theElem, alignType, PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       return NS_OK;
     }
 
@@ -4702,38 +4702,38 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
     nsCOMPtr<nsIDOMNode> brNode, parent, theDiv, sib;
     NS_NAMED_LITERAL_STRING(divType, "div");
     res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = SplitAsNeeded(&divType, address_of(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // consume a trailing br, if any.  This is to keep an alignment from
     // creating extra lines, if possible.
     res = mHTMLEditor->GetNextHTMLNode(parent, offset, address_of(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (brNode && nsTextEditUtils::IsBreak(brNode))
     {
       // making use of html structure... if next node after where
       // we are putting our div is not a block, then the br we 
       // found is in same block we are, so its safe to consume it.
       res = mHTMLEditor->GetNextHTMLSibling(parent, offset, address_of(sib));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!IsBlockNode(sib))
       {
         res = mHTMLEditor->DeleteNode(brNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     res = mHTMLEditor->CreateNode(divType, parent, offset, getter_AddRefs(theDiv));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // remember our new block for postprocessing
     mNewBlock = theDiv;
     // set up the alignment on the div, using HTML or CSS
     nsCOMPtr<nsIDOMElement> divElem = do_QueryInterface(theDiv);
     res = AlignBlock(divElem, alignType, PR_TRUE);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     *aHandled = PR_TRUE;
     // put in a moz-br so that it won't get deleted
     res = CreateMozBR(theDiv, 0, address_of(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = aSelection->Collapse(theDiv, 0);
     selectionResetter.Abort();  // don't reset our selection in this case.
     return res;
@@ -4744,7 +4744,7 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
 
   nsTArray<PRPackedBool> transitionList;
   res = MakeTransitionList(arrayOfNodes, transitionList);
-  if (NS_FAILED(res)) return res;                                 
+  NS_ENSURE_SUCCESS(res, res);                                 
 
   // Ok, now go through all the nodes and give them an align attrib or put them in a div, 
   // or whatever is appropriate.  Wohoo!
@@ -4760,7 +4760,7 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
     nsCOMPtr<nsIDOMNode> curNode = arrayOfNodes[i];
     PRInt32 offset;
     res = nsEditor::GetNodeLocation(curNode, address_of(curParent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // the node is a table element, an horiz rule, a paragraph, a div
     // or a section header; in HTML 4, it can directly carry the ALIGN
@@ -4770,7 +4770,7 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
     {
       nsCOMPtr<nsIDOMElement> curElem = do_QueryInterface(curNode);
       res = AlignBlock(curElem, alignType, PR_FALSE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // clear out curDiv so that we don't put nodes after this one into it
       curDiv = 0;
       continue;
@@ -4790,7 +4790,7 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
          || nsHTMLEditUtils::IsList(curNode))
     {
       res = RemoveAlignment(curNode, *alignType, PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (useCSS) {
         nsCOMPtr<nsIDOMElement> curElem = do_QueryInterface(curNode);
         NS_NAMED_LITERAL_STRING(attrName, "align");
@@ -4805,7 +4805,7 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
         // if we don't use CSS, add a contraint to list element : they have
         // to be inside another list, ie >= second level of nesting
         res = AlignInnerBlocks(curNode, alignType);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         curDiv = 0;
         continue;
       }
@@ -4818,9 +4818,9 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
     {
       NS_NAMED_LITERAL_STRING(divType, "div");
       res = SplitAsNeeded(&divType, address_of(curParent), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->CreateNode(divType, curParent, offset, getter_AddRefs(curDiv));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // remember our new block for postprocessing
       mNewBlock = curDiv;
       // set up the alignment on the div
@@ -4828,13 +4828,13 @@ nsHTMLEditRules::WillAlign(nsISelection *aSelection,
       res = AlignBlock(divElem, alignType, PR_TRUE);
 //      nsAutoString attr(NS_LITERAL_STRING("align"));
 //      res = mHTMLEditor->SetAttribute(divElem, attr, *alignType);
-//      if (NS_FAILED(res)) return res;
+//      NS_ENSURE_SUCCESS(res, res);
       // curDiv is now the correct thing to put curNode in
     }
 
     // tuck the node into the end of the active div
     res = mHTMLEditor->MoveNode(curNode, curDiv, -1);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   return res;
@@ -4855,9 +4855,9 @@ nsHTMLEditRules::AlignInnerBlocks(nsIDOMNode *aNode, const nsAString *alignType)
   nsTableCellAndListItemFunctor functor;
   nsDOMIterator iter;
   res = iter.Init(aNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = iter.AppendList(functor, arrayOfNodes);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // now that we have the list, align their contents as requested
   PRInt32 listCount = arrayOfNodes.Count();
@@ -4867,7 +4867,7 @@ nsHTMLEditRules::AlignInnerBlocks(nsIDOMNode *aNode, const nsAString *alignType)
   {
     nsIDOMNode* node = arrayOfNodes[0];
     res = AlignBlockContents(node, alignType);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     arrayOfNodes.RemoveObjectAt(0);
   }
 
@@ -4889,9 +4889,9 @@ nsHTMLEditRules::AlignBlockContents(nsIDOMNode *aNode, const nsAString *alignTyp
   mHTMLEditor->GetIsCSSEnabled(&useCSS);
 
   res = mHTMLEditor->GetFirstEditableChild(aNode, address_of(firstChild));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = mHTMLEditor->GetLastEditableChild(aNode, address_of(lastChild));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   NS_NAMED_LITERAL_STRING(attr, "align");
   if (!firstChild)
   {
@@ -4908,13 +4908,13 @@ nsHTMLEditRules::AlignBlockContents(nsIDOMNode *aNode, const nsAString *alignTyp
     else {
       res = mHTMLEditor->SetAttribute(divElem, attr, *alignType);
     }
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   else
   {
     // else we need to put in a div, set the alignment, and toss in all the children
     res = mHTMLEditor->CreateNode(NS_LITERAL_STRING("div"), aNode, 0, getter_AddRefs(divNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // set up the alignment on the div
     nsCOMPtr<nsIDOMElement> divElem = do_QueryInterface(divNode);
     if (useCSS) {
@@ -4923,14 +4923,14 @@ nsHTMLEditRules::AlignBlockContents(nsIDOMNode *aNode, const nsAString *alignTyp
     else {
       res = mHTMLEditor->SetAttribute(divElem, attr, *alignType);
     }
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // tuck the children into the end of the active div
     while (lastChild && (lastChild != divNode))
     {
       res = mHTMLEditor->MoveNode(lastChild, divNode, 0);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->GetLastEditableChild(aNode, address_of(lastChild));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   return res;
@@ -4958,13 +4958,13 @@ nsHTMLEditRules::CheckForEmptyBlock(nsIDOMNode *aStartNode,
   if (block != aBodyNode)  // efficiency hack. avoiding IsEmptyNode() call when in body
   {
     res = mHTMLEditor->IsEmptyNode(block, &bIsEmptyNode, PR_TRUE, PR_FALSE);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     while (bIsEmptyNode && !nsHTMLEditUtils::IsTableElement(block) && (block != aBodyNode))
     {
       emptyBlock = block;
       block = mHTMLEditor->GetBlockNodeParent(emptyBlock);
       res = mHTMLEditor->IsEmptyNode(block, &bIsEmptyNode, PR_TRUE, PR_FALSE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   
@@ -4973,7 +4973,7 @@ nsHTMLEditRules::CheckForEmptyBlock(nsIDOMNode *aStartNode,
     nsCOMPtr<nsIDOMNode> blockParent;
     PRInt32 offset;
     res = nsEditor::GetNodeLocation(emptyBlock, address_of(blockParent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!blockParent || offset < 0) return NS_ERROR_FAILURE;
 
     if (nsHTMLEditUtils::IsListItem(emptyBlock))
@@ -4981,13 +4981,13 @@ nsHTMLEditRules::CheckForEmptyBlock(nsIDOMNode *aStartNode,
       // are we the first list item in the list?
       PRBool bIsFirst;
       res = mHTMLEditor->IsFirstEditableChild(emptyBlock, &bIsFirst);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (bIsFirst)
       {
         nsCOMPtr<nsIDOMNode> listParent;
         PRInt32 listOffset;
         res = nsEditor::GetNodeLocation(blockParent, address_of(listParent), &listOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (!listParent || listOffset < 0) return NS_ERROR_FAILURE;
         // if we are a sublist, skip the br creation
         if (!nsHTMLEditUtils::IsList(listParent))
@@ -4995,10 +4995,10 @@ nsHTMLEditRules::CheckForEmptyBlock(nsIDOMNode *aStartNode,
           // create a br before list
           nsCOMPtr<nsIDOMNode> brNode;
           res = mHTMLEditor->CreateBR(listParent, listOffset, address_of(brNode));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           // adjust selection to be right before it
           res = aSelection->Collapse(listParent, listOffset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         // else just let selection perculate up.  We'll adjust it in AfterEdit()
       }
@@ -5007,7 +5007,7 @@ nsHTMLEditRules::CheckForEmptyBlock(nsIDOMNode *aStartNode,
     {
       // adjust selection to be right after it
       res = aSelection->Collapse(blockParent, offset+1);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     res = mHTMLEditor->DeleteNode(emptyBlock);
     *aHandled = PR_TRUE;
@@ -5094,7 +5094,7 @@ nsHTMLEditRules::GetInnerContent(nsIDOMNode *aNode, nsCOMArray<nsIDOMNode> &outA
        || ( aTbl && nsHTMLEditUtils::IsTableElement(node) )  )
     {
       res = GetInnerContent(node, outArrayOfNodes, aIndex, aList, aTbl);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     else
     {
@@ -5122,12 +5122,12 @@ nsHTMLEditRules::ExpandSelectionForDeletion(nsISelection *aSelection)
   // don't need to touch collapsed selections
   PRBool bCollapsed;
   nsresult res = aSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (bCollapsed) return res;
 
   PRInt32 rangeCount;
   res = aSelection->GetRangeCount(&rangeCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // we don't need to mess with cell selections, and we assume multirange selections are those.
   if (rangeCount != 1) return NS_OK;
@@ -5135,23 +5135,23 @@ nsHTMLEditRules::ExpandSelectionForDeletion(nsISelection *aSelection)
   // find current sel start and end
   nsCOMPtr<nsIDOMRange> range;
   res = aSelection->GetRangeAt(0, getter_AddRefs(range));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!range) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsIDOMNode> selStartNode, selEndNode, selCommon;
   PRInt32 selStartOffset, selEndOffset;
   
   res = range->GetStartContainer(getter_AddRefs(selStartNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = range->GetStartOffset(&selStartOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = range->GetEndContainer(getter_AddRefs(selEndNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = range->GetEndOffset(&selEndOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // find current selection common block parent
   res = range->GetCommonAncestorContainer(getter_AddRefs(selCommon));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!IsBlockNode(selCommon))
     selCommon = nsHTMLEditor::GetBlockNodeParent(selCommon);
 
@@ -5171,7 +5171,7 @@ nsHTMLEditRules::ExpandSelectionForDeletion(nsISelection *aSelection)
     {
       nsWSRunObject wsObj(mHTMLEditor, selStartNode, selStartOffset);
       res = wsObj.PriorVisibleNode(selStartNode, selStartOffset, address_of(visNode), &visOffset, &wsType);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (wsType == nsWSRunObject::eThisBlock)
       {
         // we want to keep looking up.  But stop if we are crossing table element
@@ -5202,7 +5202,7 @@ nsHTMLEditRules::ExpandSelectionForDeletion(nsISelection *aSelection)
     {
       nsWSRunObject wsObj(mHTMLEditor, selEndNode, selEndOffset);
       res = wsObj.NextVisibleNode(selEndNode, selEndOffset, address_of(visNode), &visOffset, &wsType);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (wsType == nsWSRunObject::eBreak)
       {
         if (mHTMLEditor->IsVisBreak(wsObj.mEndReasonNode))
@@ -5261,9 +5261,9 @@ nsHTMLEditRules::ExpandSelectionForDeletion(nsISelection *aSelection)
     nsCOMPtr<nsIDOMRange> range = do_CreateInstance("@mozilla.org/content/range;1");
     if (!range) return NS_ERROR_NULL_POINTER;
     res = range->SetStart(selStartNode, selStartOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = range->SetEnd(selEndNode, selEndOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     // check if block is entirely inside range
     nsCOMPtr<nsIContent> brContentBlock = do_QueryInterface(brBlock);
@@ -5298,7 +5298,7 @@ nsHTMLEditRules::AtStartOfBlock(nsIDOMNode *aNode, PRInt32 aOffset, nsIDOMNode *
   
   nsCOMPtr<nsIDOMNode> priorNode;
   nsresult  res = mHTMLEditor->GetPriorHTMLNode(aNode, aOffset, address_of(priorNode));
-  if (NS_FAILED(res)) return PR_TRUE;
+  NS_ENSURE_SUCCESS(res, PR_TRUE);
   if (!priorNode) return PR_TRUE;
   nsCOMPtr<nsIDOMNode> blockParent = mHTMLEditor->GetBlockNodeParent(priorNode);
   if (blockParent && (blockParent == aBlock)) return PR_FALSE;
@@ -5321,7 +5321,7 @@ nsHTMLEditRules::AtEndOfBlock(nsIDOMNode *aNode, PRInt32 aOffset, nsIDOMNode *aB
   }
   nsCOMPtr<nsIDOMNode> nextNode;
   nsresult  res = mHTMLEditor->GetNextHTMLNode(aNode, aOffset, address_of(nextNode));
-  if (NS_FAILED(res)) return PR_TRUE;
+  NS_ENSURE_SUCCESS(res, PR_TRUE);
   if (!nextNode) return PR_TRUE;
   nsCOMPtr<nsIDOMNode> blockParent = mHTMLEditor->GetBlockNodeParent(nextNode);
   if (blockParent && (blockParent == aBlock)) return PR_FALSE;
@@ -5339,11 +5339,11 @@ nsHTMLEditRules::CreateMozDiv(nsIDOMNode *inParent, PRInt32 inOffset, nsCOMPtr<n
   nsAutoString divType= "div";
   *outDiv = nsnull;
   nsresult res = mHTMLEditor->CreateNode(divType, inParent, inOffset, getter_AddRefs(*outDiv));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // give it special moz attr
   nsCOMPtr<nsIDOMElement> mozDivElem = do_QueryInterface(*outDiv);
   res = mHTMLEditor->SetAttribute(mozDivElem, "type", "_moz");
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = AddTrailerBR(*outDiv);
   return res;
 }
@@ -5365,19 +5365,19 @@ nsHTMLEditRules::NormalizeSelection(nsISelection *inSelection)
   // don't need to touch collapsed selections
   PRBool bCollapsed;
   nsresult res = inSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (bCollapsed) return res;
 
   PRInt32 rangeCount;
   res = inSelection->GetRangeCount(&rangeCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // we don't need to mess with cell selections, and we assume multirange selections are those.
   if (rangeCount != 1) return NS_OK;
   
   nsCOMPtr<nsIDOMRange> range;
   res = inSelection->GetRangeAt(0, getter_AddRefs(range));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!range) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsIDOMNode> startNode, endNode;
   PRInt32 startOffset, endOffset;
@@ -5385,13 +5385,13 @@ nsHTMLEditRules::NormalizeSelection(nsISelection *inSelection)
   PRInt32 newStartOffset, newEndOffset;
   
   res = range->GetStartContainer(getter_AddRefs(startNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = range->GetStartOffset(&startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = range->GetEndContainer(getter_AddRefs(endNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = range->GetEndOffset(&endOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // adjusted values default to original values
   newStartNode = startNode; 
@@ -5409,7 +5409,7 @@ nsHTMLEditRules::NormalizeSelection(nsISelection *inSelection)
   // is there any intervening visible whitespace?  if so we can't push selection past that,
   // it would visibly change maening of users selection
   res = wsEndObj.PriorVisibleNode(endNode, endOffset, address_of(someNode), &offset, &wsType);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if ((wsType != nsWSRunObject::eText) && (wsType != nsWSRunObject::eNormalWS))
   {
     // eThisBlock and eOtherBlock conveniently distinquish cases
@@ -5421,7 +5421,7 @@ nsHTMLEditRules::NormalizeSelection(nsISelection *inSelection)
       if (child)
       {
         res = nsEditor::GetNodeLocation(child, address_of(newEndNode), &newEndOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         ++newEndOffset; // offset *after* child
       }
       // else block is empty - we can leave selection alone here, i think.
@@ -5434,7 +5434,7 @@ nsHTMLEditRules::NormalizeSelection(nsISelection *inSelection)
       if (child)
       {
         res = nsEditor::GetNodeLocation(child, address_of(newEndNode), &newEndOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         ++newEndOffset; // offset *after* child
       }
       // else block is empty - we can leave selection alone here, i think.
@@ -5443,7 +5443,7 @@ nsHTMLEditRules::NormalizeSelection(nsISelection *inSelection)
     {                                       
       // endpoint is just after break.  lets adjust it to before it.
       res = nsEditor::GetNodeLocation(wsEndObj.mStartReasonNode, address_of(newEndNode), &newEndOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   
@@ -5453,7 +5453,7 @@ nsHTMLEditRules::NormalizeSelection(nsISelection *inSelection)
   // is there any intervening visible whitespace?  if so we can't push selection past that,
   // it would visibly change maening of users selection
   res = wsStartObj.NextVisibleNode(startNode, startOffset, address_of(someNode), &offset, &wsType);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if ((wsType != nsWSRunObject::eText) && (wsType != nsWSRunObject::eNormalWS))
   {
     // eThisBlock and eOtherBlock conveniently distinquish cases
@@ -5465,7 +5465,7 @@ nsHTMLEditRules::NormalizeSelection(nsISelection *inSelection)
       if (child)
       {
         res = nsEditor::GetNodeLocation(child, address_of(newStartNode), &newStartOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       // else block is empty - we can leave selection alone here, i think.
     }
@@ -5477,7 +5477,7 @@ nsHTMLEditRules::NormalizeSelection(nsISelection *inSelection)
       if (child)
       {
         res = nsEditor::GetNodeLocation(child, address_of(newStartNode), &newStartOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       // else block is empty - we can leave selection alone here, i think.
     }
@@ -5485,7 +5485,7 @@ nsHTMLEditRules::NormalizeSelection(nsISelection *inSelection)
     {                                       
       // startpoint is just before a break.  lets adjust it to after it.
       res = nsEditor::GetNodeLocation(wsStartObj.mEndReasonNode, address_of(newStartNode), &newStartOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       ++newStartOffset; // offset *after* break
     }
   }
@@ -5540,7 +5540,7 @@ nsHTMLEditRules::GetPromotedPoint(RulesEndpoint aWhere, nsIDOMNode *aNode, PRInt
       do
       {
         res = mHTMLEditor->IsPrevCharWhitespace(node, offset, &isSpace, &isNBSP, address_of(temp), &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (isSpace || isNBSP) node = temp;
         else break;
       } while (node);
@@ -5553,7 +5553,7 @@ nsHTMLEditRules::GetPromotedPoint(RulesEndpoint aWhere, nsIDOMNode *aNode, PRInt
       do
       {
         res = mHTMLEditor->IsNextCharWhitespace(node, offset, &isSpace, &isNBSP, address_of(temp), &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (isSpace || isNBSP) node = temp;
         else break;
       } while (node);
@@ -5572,7 +5572,7 @@ nsHTMLEditRules::GetPromotedPoint(RulesEndpoint aWhere, nsIDOMNode *aNode, PRInt
     if (nsEditor::IsTextNode(aNode))  
     {
       res = nsEditor::GetNodeLocation(aNode, address_of(node), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
 
     // look back through any further inline nodes that
@@ -5587,16 +5587,16 @@ nsHTMLEditRules::GetPromotedPoint(RulesEndpoint aWhere, nsIDOMNode *aNode, PRInt
       if (IsBlockNode(priorNode))
         break;
       res = nsEditor::GetNodeLocation(priorNode, address_of(node), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->GetPriorHTMLNode(node, offset, address_of(priorNode), PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     
         
     // finding the real start for this point.  look up the tree for as long as we are the 
     // first node in the container, and as long as we haven't hit the body node.
     res = mHTMLEditor->GetPriorHTMLNode(node, offset, address_of(nearNode), PR_TRUE);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     while (!nearNode && !nsTextEditUtils::IsBody(node))
     {
       // some cutoffs are here: we don't need to also include them in the aWhere == kEnd case.
@@ -5607,11 +5607,11 @@ nsHTMLEditRules::GetPromotedPoint(RulesEndpoint aWhere, nsIDOMNode *aNode, PRInt
         break;
 
       res = nsEditor::GetNodeLocation(node, address_of(parent), &pOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       node = parent;
       offset = pOffset;
       res = mHTMLEditor->GetPriorHTMLNode(node, offset, address_of(nearNode), PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     } 
     *outNode = node;
     *outOffset = offset;
@@ -5624,7 +5624,7 @@ nsHTMLEditRules::GetPromotedPoint(RulesEndpoint aWhere, nsIDOMNode *aNode, PRInt
     if (nsEditor::IsTextNode(aNode))  
     {
       res = nsEditor::GetNodeLocation(aNode, address_of(node), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       offset++; // want to be after the text node
     }
 
@@ -5638,26 +5638,26 @@ nsHTMLEditRules::GetPromotedPoint(RulesEndpoint aWhere, nsIDOMNode *aNode, PRInt
       if (IsBlockNode(nextNode))
         break;
       res = nsEditor::GetNodeLocation(nextNode, address_of(node), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       offset++;
       if (mHTMLEditor->IsVisBreak(nextNode))
         break;
       res = mHTMLEditor->GetNextHTMLNode(node, offset, address_of(nextNode), PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     
     // finding the real end for this point.  look up the tree for as long as we are the 
     // last node in the container, and as long as we haven't hit the body node.
     res = mHTMLEditor->GetNextHTMLNode(node, offset, address_of(nearNode), PR_TRUE);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     while (!nearNode && !nsTextEditUtils::IsBody(node))
     {
       res = nsEditor::GetNodeLocation(node, address_of(parent), &pOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       node = parent;
       offset = pOffset+1;  // we want to be AFTER nearNode
       res = mHTMLEditor->GetNextHTMLNode(node, offset, address_of(nearNode), PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     } 
     *outNode = node;
     *outOffset = offset;
@@ -5681,7 +5681,7 @@ nsHTMLEditRules::GetPromotedRanges(nsISelection *inSelection,
 
   PRInt32 rangeCount;
   nsresult res = inSelection->GetRangeCount(&rangeCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   PRInt32 i;
   nsCOMPtr<nsIDOMRange> selectionRange;
@@ -5690,18 +5690,18 @@ nsHTMLEditRules::GetPromotedRanges(nsISelection *inSelection,
   for (i = 0; i < rangeCount; i++)
   {
     res = inSelection->GetRangeAt(i, getter_AddRefs(selectionRange));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // clone range so we don't muck with actual selection ranges
     res = selectionRange->CloneRange(getter_AddRefs(opRange));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // make a new adjusted range to represent the appropriate block content.
     // The basic idea is to push out the range endpoints
     // to truly enclose the blocks that we will affect.
     // This call alters opRange.
     res = PromoteRange(opRange, inOperationType);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
       
     // stuff new opRange into array
     outArrayOfRanges.AppendObject(opRange);
@@ -5724,13 +5724,13 @@ nsHTMLEditRules::PromoteRange(nsIDOMRange *inRange,
   PRInt32 startOffset, endOffset;
   
   res = inRange->GetStartContainer(getter_AddRefs(startNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetStartOffset(&startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetEndContainer(getter_AddRefs(endNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetEndOffset(&endOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // MOOSE major hack:
   // GetPromotedPoint doesn't really do the right thing for collapsed ranges
@@ -5777,11 +5777,11 @@ nsHTMLEditRules::PromoteRange(nsIDOMRange *inRange,
   nsCOMPtr<nsIDOMRange> opRange;
   
   res = GetPromotedPoint( kStart, startNode, startOffset, inOperationType, address_of(opStartNode), &opStartOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = GetPromotedPoint( kEnd, endNode, endOffset, inOperationType, address_of(opEndNode), &opEndOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->SetStart(opStartNode, opStartOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->SetEnd(opEndNode, opEndOffset);
   return res;
 } 
@@ -5861,7 +5861,7 @@ nsHTMLEditRules::GetNodesForOperation(nsCOMArray<nsIDOMRange>& inArrayOfRanges,
       }
       inArrayOfRanges.AppendObject(opRange);
     }
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   // gather up a list of all the nodes
   for (i = 0; i < rangeCount; i++)
@@ -5870,11 +5870,11 @@ nsHTMLEditRules::GetNodesForOperation(nsCOMArray<nsIDOMRange>& inArrayOfRanges,
     
     nsDOMSubtreeIterator iter;
     res = iter.Init(opRange);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (outArrayOfNodes.Count() == 0) {
       nsTrivialFunctor functor;
       res = iter.AppendList(functor, outArrayOfNodes);
-      if (NS_FAILED(res)) return res;    
+      NS_ENSURE_SUCCESS(res, res);    
     }
     else {
       // We don't want duplicates in outArrayOfNodes, so we use an
@@ -5883,7 +5883,7 @@ nsHTMLEditRules::GetNodesForOperation(nsCOMArray<nsIDOMRange>& inArrayOfRanges,
       nsCOMArray<nsIDOMNode> nodes;
       nsUniqueFunctor functor(outArrayOfNodes);
       res = iter.AppendList(functor, nodes);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!outArrayOfNodes.AppendObjects(nodes))
         return NS_ERROR_OUT_OF_MEMORY;
     }
@@ -5902,7 +5902,7 @@ nsHTMLEditRules::GetNodesForOperation(nsCOMArray<nsIDOMRange>& inArrayOfRanges,
         PRInt32 j=i;
         outArrayOfNodes.RemoveObjectAt(i);
         res = GetInnerContent(node, outArrayOfNodes, &j);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
   }
@@ -5921,7 +5921,7 @@ nsHTMLEditRules::GetNodesForOperation(nsCOMArray<nsIDOMRange>& inArrayOfRanges,
         PRInt32 j=i;
         outArrayOfNodes.RemoveObjectAt(i);
         res = GetInnerContent(node, outArrayOfNodes, &j);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
   }
@@ -5937,7 +5937,7 @@ nsHTMLEditRules::GetNodesForOperation(nsCOMArray<nsIDOMRange>& inArrayOfRanges,
         PRInt32 j=i;
         outArrayOfNodes.RemoveObjectAt(i);
         res = GetInnerContent(node, outArrayOfNodes, &j, PR_FALSE, PR_FALSE);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
   }
@@ -5961,7 +5961,7 @@ nsHTMLEditRules::GetNodesForOperation(nsCOMArray<nsIDOMRange>& inArrayOfRanges,
       {
         nsCOMArray<nsIDOMNode> arrayOfInlines;
         res = BustUpInlinesAtBRs(node, arrayOfInlines);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // put these nodes in outArrayOfNodes, replacing the current node
         outArrayOfNodes.RemoveObjectAt(i);
         outArrayOfNodes.InsertObjectsAt(arrayOfInlines, i);
@@ -5984,11 +5984,11 @@ nsHTMLEditRules::GetChildNodesForOperation(nsIDOMNode *inNode,
   
   nsCOMPtr<nsIDOMNodeList> childNodes;
   nsresult res = inNode->GetChildNodes(getter_AddRefs(childNodes));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!childNodes) return NS_ERROR_NULL_POINTER;
   PRUint32 childCount;
   res = childNodes->GetLength(&childCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   PRUint32 i;
   nsCOMPtr<nsIDOMNode> node;
@@ -6016,7 +6016,7 @@ nsHTMLEditRules::GetListActionNodes(nsCOMArray<nsIDOMNode> &outArrayOfNodes,
   
   nsCOMPtr<nsISelection>selection;
   res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));
   if (!selPriv)
     return NS_ERROR_FAILURE;
@@ -6026,14 +6026,14 @@ nsHTMLEditRules::GetListActionNodes(nsCOMArray<nsIDOMNode> &outArrayOfNodes,
   {       
     nsCOMPtr<nsIEnumerator> enumerator;
     res = selPriv->GetEnumerator(getter_AddRefs(enumerator));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!enumerator) return NS_ERROR_UNEXPECTED;
 
     for (enumerator->First(); NS_OK!=enumerator->IsDone(); enumerator->Next())
     {
       nsCOMPtr<nsISupports> currentItem;
       res = enumerator->CurrentItem(getter_AddRefs(currentItem));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!currentItem) return NS_ERROR_UNEXPECTED;
 
       nsCOMPtr<nsIDOMRange> range( do_QueryInterface(currentItem) );
@@ -6061,7 +6061,7 @@ nsHTMLEditRules::GetListActionNodes(nsCOMArray<nsIDOMNode> &outArrayOfNodes,
   
   // contruct a list of nodes to act on.
   res = GetNodesFromSelection(selection, kMakeList, outArrayOfNodes, aDontTouchContent);
-  if (NS_FAILED(res)) return res;                                 
+  NS_ENSURE_SUCCESS(res, res);                                 
                
   // pre process our list of nodes...                      
   PRInt32 listCount = outArrayOfNodes.Count();
@@ -6083,7 +6083,7 @@ nsHTMLEditRules::GetListActionNodes(nsCOMArray<nsIDOMNode> &outArrayOfNodes,
       PRInt32 j=i;
       outArrayOfNodes.RemoveObjectAt(i);
       res = GetInnerContent(testNode, outArrayOfNodes, &j, PR_FALSE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
 
@@ -6115,7 +6115,7 @@ nsHTMLEditRules::LookInsideDivBQandList(nsCOMArray<nsIDOMNode>& aNodeArray)
       // dive as long as there is only one child, and it is a list, div, blockquote
       PRUint32 numChildren;
       res = mHTMLEditor->CountEditableChildren(curNode, numChildren);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       
       if (numChildren == 1)
       {
@@ -6179,11 +6179,11 @@ nsHTMLEditRules::GetParagraphFormatNodes(nsCOMArray<nsIDOMNode>& outArrayOfNodes
 {  
   nsCOMPtr<nsISelection>selection;
   nsresult res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // contruct a list of nodes to act on.
   res = GetNodesFromSelection(selection, kMakeBasicBlock, outArrayOfNodes, aDontTouchContent);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // pre process our list of nodes...                      
   PRInt32 listCount = outArrayOfNodes.Count();
@@ -6207,7 +6207,7 @@ nsHTMLEditRules::GetParagraphFormatNodes(nsCOMArray<nsIDOMNode>& outArrayOfNodes
       PRInt32 j=i;
       outArrayOfNodes.RemoveObjectAt(i);
       res = GetInnerContent(testNode, outArrayOfNodes, &j);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   return res;
@@ -6233,7 +6233,7 @@ nsHTMLEditRules::BustUpInlinesAtRangeEndpoints(nsRangeStore &item)
     endInline->GetParentNode(getter_AddRefs(resultEndNode));
     res = mHTMLEditor->SplitNodeDeep(endInline, item.endNode, item.endOffset,
                           &resultEndOffset, PR_TRUE);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // reset range
     item.endNode = resultEndNode; item.endOffset = resultEndOffset;
   }
@@ -6247,7 +6247,7 @@ nsHTMLEditRules::BustUpInlinesAtRangeEndpoints(nsRangeStore &item)
     startInline->GetParentNode(getter_AddRefs(resultStartNode));
     res = mHTMLEditor->SplitNodeDeep(startInline, item.startNode, item.startOffset,
                           &resultStartOffset, PR_TRUE);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // reset range
     item.startNode = resultStartNode; item.startOffset = resultStartOffset;
   }
@@ -6272,9 +6272,9 @@ nsHTMLEditRules::BustUpInlinesAtBRs(nsIDOMNode *inNode,
   nsBRNodeFunctor functor;
   nsDOMIterator iter;
   nsresult res = iter.Init(inNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = iter.AppendList(functor, arrayOfBreaks);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // if there aren't any breaks, just put inNode itself in the array
   PRInt32 listCount = arrayOfBreaks.Count();
@@ -6301,10 +6301,10 @@ nsHTMLEditRules::BustUpInlinesAtBRs(nsIDOMNode *inNode,
       if (!breakNode) return NS_ERROR_NULL_POINTER;
       if (!splitDeepNode) return NS_ERROR_NULL_POINTER;
       res = nsEditor::GetNodeLocation(breakNode, address_of(splitParentNode), &splitOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->SplitNodeDeep(splitDeepNode, splitParentNode, splitOffset,
                           &resultOffset, PR_FALSE, address_of(leftNode), address_of(rightNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // put left node in node list
       if (leftNode)
       {
@@ -6316,7 +6316,7 @@ nsHTMLEditRules::BustUpInlinesAtBRs(nsIDOMNode *inNode,
       }
       // move break outside of container and also put in node list
       res = mHTMLEditor->MoveNode(breakNode, inlineParentNode, resultOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!outArrayOfNodes.AppendObject(breakNode))
         return  NS_ERROR_FAILURE;
       // now rightNode becomes the new node to split
@@ -6369,14 +6369,14 @@ nsHTMLEditRules::GetNodesFromPoint(DOMPoint point,
   // use it to make a range
   nsCOMPtr<nsIDOMRange> range = do_CreateInstance("@mozilla.org/content/range;1");
   res = range->SetStart(node, offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   /* SetStart() will also set the end for this new range
   res = range->SetEnd(node, offset);
-  if (NS_FAILED(res)) return res; */
+  NS_ENSURE_SUCCESS(res, res); */
   
   // expand the range to include adjacent inlines
   res = PromoteRange(range, operation);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
       
   // make array of ranges
   nsCOMArray<nsIDOMRange> arrayOfRanges;
@@ -6406,7 +6406,7 @@ nsHTMLEditRules::GetNodesFromSelection(nsISelection *selection,
   // promote selection ranges
   nsCOMArray<nsIDOMRange> arrayOfRanges;
   res = GetPromotedRanges(selection, arrayOfRanges, operation);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // use these ranges to contruct a list of nodes to act on.
   res = GetNodesForOperation(arrayOfRanges, arrayOfNodes, operation, dontTouchContent); 
@@ -6493,17 +6493,17 @@ nsHTMLEditRules::ReturnInHeader(nsISelection *aSelection,
   nsCOMPtr<nsIDOMNode> headerParent;
   PRInt32 offset;
   nsresult res = nsEditor::GetNodeLocation(aHeader, address_of(headerParent), &offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // get ws code to adjust any ws
   nsCOMPtr<nsIDOMNode> selNode = aNode;
   res = nsWSRunObject::PrepareToSplitAcrossBlocks(mHTMLEditor, address_of(selNode), &aOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // split the header
   PRInt32 newOffset;
   res = mHTMLEditor->SplitNodeDeep( aHeader, selNode, aOffset, &newOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // if the leftand heading is empty, put a mozbr in it
   nsCOMPtr<nsIDOMNode> prevItem;
@@ -6512,35 +6512,35 @@ nsHTMLEditRules::ReturnInHeader(nsISelection *aSelection,
   {
     PRBool bIsEmptyNode;
     res = mHTMLEditor->IsEmptyNode(prevItem, &bIsEmptyNode);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (bIsEmptyNode)
     {
       nsCOMPtr<nsIDOMNode> brNode;
       res = CreateMozBR(prevItem, 0, address_of(brNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   
   // if the new (righthand) header node is empty, delete it
   PRBool isEmpty;
   res = IsEmptyBlock(aHeader, &isEmpty, PR_TRUE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (isEmpty)
   {
     res = mHTMLEditor->DeleteNode(aHeader);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // layout tells the caret to blink in a weird place
     // if we don't place a break after the header.
     nsCOMPtr<nsIDOMNode> sibling;
     res = mHTMLEditor->GetNextHTMLSibling(headerParent, offset+1, address_of(sibling));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!sibling || !nsTextEditUtils::IsBreak(sibling))
     {
       res = CreateMozBR(headerParent, offset+1, address_of(sibling));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     res = nsEditor::GetNodeLocation(sibling, address_of(headerParent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // put selection after break
     res = aSelection->Collapse(headerParent,offset+1);
   }
@@ -6571,11 +6571,11 @@ nsHTMLEditRules::ReturnInParagraph(nsISelection *aSelection,
   nsCOMPtr<nsIDOMNode> parent;
   PRInt32 offset;
   nsresult res = nsEditor::GetNodeLocation(aNode, address_of(parent), &offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   PRBool  doesCRCreateNewP;
   res = mHTMLEditor->GetReturnInParagraphCreatesNewParagraph(&doesCRCreateNewP);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   PRBool newBRneeded = PR_FALSE;
   nsCOMPtr<nsIDOMNode> sibling;
@@ -6589,7 +6589,7 @@ nsHTMLEditRules::ReturnInParagraph(nsISelection *aSelection,
     nsCOMPtr<nsIDOMText> textNode = do_QueryInterface(aNode);
     PRUint32 strLength;
     res = textNode->GetLength(&strLength);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     // at beginning of text node?
     if (!aOffset)
@@ -6620,7 +6620,7 @@ nsHTMLEditRules::ReturnInParagraph(nsISelection *aSelection,
       {
         nsCOMPtr<nsIDOMNode> tmp;
         res = mEditor->SplitNode(aNode, aOffset, getter_AddRefs(tmp));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         aNode = tmp;
       }
 
@@ -6634,12 +6634,12 @@ nsHTMLEditRules::ReturnInParagraph(nsISelection *aSelection,
     // is there a BR prior to it?
     nsCOMPtr<nsIDOMNode> nearNode, selNode = aNode;
     res = mHTMLEditor->GetPriorHTMLNode(aNode, aOffset, address_of(nearNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!nearNode || !mHTMLEditor->IsVisBreak(nearNode) || nsTextEditUtils::HasMozAttr(nearNode)) 
     {
       // is there a BR after it?
       res = mHTMLEditor->GetNextHTMLNode(aNode, aOffset, address_of(nearNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!nearNode || !mHTMLEditor->IsVisBreak(nearNode) || nsTextEditUtils::HasMozAttr(nearNode)) 
       {
         newBRneeded = PR_TRUE;
@@ -6682,23 +6682,23 @@ nsHTMLEditRules::SplitParagraph(nsIDOMNode *aPara,
   // get ws code to adjust any ws
   nsCOMPtr<nsIDOMNode> leftPara, rightPara;
   res = nsWSRunObject::PrepareToSplitAcrossBlocks(mHTMLEditor, aSelNode, aOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // split the paragraph
   res = mHTMLEditor->SplitNodeDeep(aPara, *aSelNode, *aOffset, &newOffset, PR_FALSE,
                                    address_of(leftPara), address_of(rightPara));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // get rid of the break, if it is visible (otherwise it may be needed to prevent an empty p)
   if (mHTMLEditor->IsVisBreak(aBRNode))
   {
     res = mHTMLEditor->DeleteNode(aBRNode);  
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   // check both halves of para to see if we need mozBR
   res = InsertMozBRIfNeeded(leftPara);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = InsertMozBRIfNeeded(rightPara);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // selection to beginning of right hand para;
   // look inside any containers that are up front.
@@ -6741,45 +6741,45 @@ nsHTMLEditRules::ReturnInListItem(nsISelection *aSelection,
   // if we are in an empty listitem, then we want to pop up out of the list
   PRBool isEmpty;
   res = IsEmptyBlock(aListItem, &isEmpty, PR_TRUE, PR_FALSE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (isEmpty && mReturnInEmptyLIKillsList)   // but only if prefs says it's ok
   {
     nsCOMPtr<nsIDOMNode> list, listparent;
     PRInt32 offset, itemOffset;
     res = nsEditor::GetNodeLocation(aListItem, address_of(list), &itemOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = nsEditor::GetNodeLocation(list, address_of(listparent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     // are we the last list item in the list?
     PRBool bIsLast;
     res = mHTMLEditor->IsLastEditableChild(aListItem, &bIsLast);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!bIsLast)
     {
       // we need to split the list!
       nsCOMPtr<nsIDOMNode> tempNode;
       res = mHTMLEditor->SplitNode(list, itemOffset, getter_AddRefs(tempNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     // are we in a sublist?
     if (nsHTMLEditUtils::IsList(listparent))  //in a sublist
     {
       // if so, move this list item out of this list and into the grandparent list
       res = mHTMLEditor->MoveNode(aListItem,listparent,offset+1);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = aSelection->Collapse(aListItem,0);
     }
     else
     {
       // otherwise kill this listitem
       res = mHTMLEditor->DeleteNode(aListItem);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       
       // time to insert a break
       nsCOMPtr<nsIDOMNode> brNode;
       res = CreateMozBR(listparent, offset+1, address_of(brNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       
       // set selection to before the moz br
       selPriv->SetInterlinePosition(PR_TRUE);
@@ -6792,11 +6792,11 @@ nsHTMLEditRules::ReturnInListItem(nsISelection *aSelection,
   // get ws code to adjust any ws
   nsCOMPtr<nsIDOMNode> selNode = aNode;
   res = nsWSRunObject::PrepareToSplitAcrossBlocks(mHTMLEditor, address_of(selNode), &aOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // now split list item
   PRInt32 newOffset;
   res = mHTMLEditor->SplitNodeDeep( aListItem, selNode, aOffset, &newOffset, PR_FALSE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // hack: until I can change the damaged doc range code back to being
   // extra inclusive, I have to manually detect certain list items that
   // may be left empty.
@@ -6807,17 +6807,17 @@ nsHTMLEditRules::ReturnInListItem(nsISelection *aSelection,
   {
     PRBool bIsEmptyNode;
     res = mHTMLEditor->IsEmptyNode(prevItem, &bIsEmptyNode);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (bIsEmptyNode)
     {
       nsCOMPtr<nsIDOMNode> brNode;
       res = CreateMozBR(prevItem, 0, address_of(brNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     else 
     {
       res = mHTMLEditor->IsEmptyNode(aListItem, &bIsEmptyNode, PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (bIsEmptyNode) 
       {
         nsCOMPtr<nsIAtom> nodeAtom = nsEditor::GetTag(aListItem);
@@ -6826,20 +6826,20 @@ nsHTMLEditRules::ReturnInListItem(nsISelection *aSelection,
           nsCOMPtr<nsIDOMNode> list;
           PRInt32 itemOffset;
           res = nsEditor::GetNodeLocation(aListItem, address_of(list), &itemOffset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
 
           nsAutoString listTag((nodeAtom == nsEditProperty::dt) ? NS_LITERAL_STRING("dd") : NS_LITERAL_STRING("dt"));
           nsCOMPtr<nsIDOMNode> newListItem;
           res = mHTMLEditor->CreateNode(listTag, list, itemOffset+1, getter_AddRefs(newListItem));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = mEditor->DeleteNode(aListItem);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           return aSelection->Collapse(newListItem, 0);
         }
 
         nsCOMPtr<nsIDOMNode> brNode;
         res = mHTMLEditor->CopyLastEditableChildStyles(prevItem, aListItem, getter_AddRefs(brNode));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (brNode) 
         {
           nsCOMPtr<nsIDOMNode> brParent;
@@ -6855,7 +6855,7 @@ nsHTMLEditRules::ReturnInListItem(nsISelection *aSelection,
         PRInt32 visOffset = 0;
         PRInt16 wsType;
         res = wsObj.NextVisibleNode(aListItem, 0, address_of(visNode), &visOffset, &wsType);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if ( (wsType==nsWSRunObject::eSpecial)  || 
              (wsType==nsWSRunObject::eBreak)    ||
              nsHTMLEditUtils::IsHR(visNode) ) 
@@ -6863,7 +6863,7 @@ nsHTMLEditRules::ReturnInListItem(nsISelection *aSelection,
           nsCOMPtr<nsIDOMNode> parent;
           PRInt32 offset;
           res = nsEditor::GetNodeLocation(visNode, address_of(parent), &offset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           return aSelection->Collapse(parent, offset);
         }
         else
@@ -6903,7 +6903,7 @@ nsHTMLEditRules::MakeBlockquote(nsCOMArray<nsIDOMNode>& arrayOfNodes)
     // get the node to act on, and it's location
     curNode = arrayOfNodes[i];
     res = nsEditor::GetNodeLocation(curNode, address_of(curParent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // if the node is a table element or list item, dive inside
     if (nsHTMLEditUtils::IsTableElementButNotTable(curNode) || 
@@ -6913,9 +6913,9 @@ nsHTMLEditRules::MakeBlockquote(nsCOMArray<nsIDOMNode>& arrayOfNodes)
       // recursion time
       nsCOMArray<nsIDOMNode> childArray;
       res = GetChildNodesForOperation(curNode, childArray);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = MakeBlockquote(childArray);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     
     // if the node has different parent than previous node,
@@ -6941,16 +6941,16 @@ nsHTMLEditRules::MakeBlockquote(nsCOMArray<nsIDOMNode>& arrayOfNodes)
     {
       NS_NAMED_LITERAL_STRING(quoteType, "blockquote");
       res = SplitAsNeeded(&quoteType, address_of(curParent), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->CreateNode(quoteType, curParent, offset, getter_AddRefs(curBlock));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // remember our new block for postprocessing
       mNewBlock = curBlock;
       // note: doesn't matter if we set mNewBlock multiple times.
     }
       
     res = mHTMLEditor->MoveNode(curNode, curBlock, -1);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return res;
 }
@@ -6979,7 +6979,7 @@ nsHTMLEditRules::RemoveBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes)
     // get the node to act on, and it's location
     curNode = arrayOfNodes[i];
     res = nsEditor::GetNodeLocation(curNode, address_of(curParent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     nsAutoString curNodeTag, curBlockTag;
     nsEditor::GetTagString(curNode, curNodeTag);
     ToLowerCase(curNodeTag);
@@ -6991,12 +6991,12 @@ nsHTMLEditRules::RemoveBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes)
       if (curBlock)
       {
         res = RemovePartOfBlock(curBlock, firstNode, lastNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         curBlock = 0;  firstNode = 0;  lastNode = 0;
       }
       // remove curent block
       res = mHTMLEditor->RemoveBlockContainer(curNode); 
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     else if (nsHTMLEditUtils::IsTable(curNode)                    || 
              nsHTMLEditUtils::IsTableRow(curNode)                 ||
@@ -7011,15 +7011,15 @@ nsHTMLEditRules::RemoveBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes)
       if (curBlock)
       {
         res = RemovePartOfBlock(curBlock, firstNode, lastNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         curBlock = 0;  firstNode = 0;  lastNode = 0;
       }
       // recursion time
       nsCOMArray<nsIDOMNode> childArray;
       res = GetChildNodesForOperation(curNode, childArray);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = RemoveBlockStyle(childArray);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     else if (IsInlineNode(curNode))
     {
@@ -7037,7 +7037,7 @@ nsHTMLEditRules::RemoveBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes)
           // so lets handle it now.  We need to remove the portion of 
           // curBlock that contains [firstNode - lastNode].
           res = RemovePartOfBlock(curBlock, firstNode, lastNode);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           curBlock = 0;  firstNode = 0;  lastNode = 0;
           // fall out and handle curNode
         }
@@ -7057,7 +7057,7 @@ nsHTMLEditRules::RemoveBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes)
       if (curBlock)
       {
         res = RemovePartOfBlock(curBlock, firstNode, lastNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         curBlock = 0;  firstNode = 0;  lastNode = 0;
       }
     }
@@ -7066,7 +7066,7 @@ nsHTMLEditRules::RemoveBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes)
   if (curBlock)
   {
     res = RemovePartOfBlock(curBlock, firstNode, lastNode);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     curBlock = 0;  firstNode = 0;  lastNode = 0;
   }
   return res;
@@ -7111,7 +7111,7 @@ nsHTMLEditRules::ApplyBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes, const nsA
     // get the node to act on, and it's location
     curNode = arrayOfNodes[i];
     res = nsEditor::GetNodeLocation(curNode, address_of(curParent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     nsAutoString curNodeTag;
     nsEditor::GetTagString(curNode, curNodeTag);
     ToLowerCase(curNodeTag);
@@ -7132,7 +7132,7 @@ nsHTMLEditRules::ApplyBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes, const nsA
       curBlock = 0;  // forget any previous block used for previous inline nodes
       res = mHTMLEditor->ReplaceContainer(curNode, address_of(newBlock), *aBlockTag,
                                           nsnull, nsnull, PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     else if (nsHTMLEditUtils::IsTable(curNode)                    || 
              (curNodeTag.EqualsLiteral("tbody"))      ||
@@ -7147,21 +7147,21 @@ nsHTMLEditRules::ApplyBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes, const nsA
       // recursion time
       nsCOMArray<nsIDOMNode> childArray;
       res = GetChildNodesForOperation(curNode, childArray);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       PRInt32 childCount = childArray.Count();
       if (childCount)
       {
         res = ApplyBlockStyle(childArray, aBlockTag);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       else
       {
         // make sure we can put a block here
         res = SplitAsNeeded(aBlockTag, address_of(curParent), &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         nsCOMPtr<nsIDOMNode> theBlock;
         res = mHTMLEditor->CreateNode(*aBlockTag, curParent, offset, getter_AddRefs(theBlock));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // remember our new block for postprocessing
         mNewBlock = theBlock;
       }
@@ -7174,21 +7174,21 @@ nsHTMLEditRules::ApplyBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes, const nsA
       {
         curBlock = 0;  // forget any previous block used for previous inline nodes
         res = mHTMLEditor->DeleteNode(curNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       else
       {
         // the break is the first (or even only) node we encountered.  Create a
         // block for it.
         res = SplitAsNeeded(aBlockTag, address_of(curParent), &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = mHTMLEditor->CreateNode(*aBlockTag, curParent, offset, getter_AddRefs(curBlock));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // remember our new block for postprocessing
         mNewBlock = curBlock;
         // note: doesn't matter if we set mNewBlock multiple times.
         res = mHTMLEditor->MoveNode(curNode, curBlock, -1);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
         
@@ -7211,9 +7211,9 @@ nsHTMLEditRules::ApplyBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes, const nsA
       if (!curBlock)
       {
         res = SplitAsNeeded(aBlockTag, address_of(curParent), &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = mHTMLEditor->CreateNode(*aBlockTag, curParent, offset, getter_AddRefs(curBlock));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // remember our new block for postprocessing
         mNewBlock = curBlock;
         // note: doesn't matter if we set mNewBlock multiple times.
@@ -7225,7 +7225,7 @@ nsHTMLEditRules::ApplyBlockStyle(nsCOMArray<nsIDOMNode>& arrayOfNodes, const nsA
       // this is a continuation of some inline nodes that belong together in
       // the same block item.  use curBlock
       res = mHTMLEditor->MoveNode(curNode, curBlock, -1);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   return res;
@@ -7270,7 +7270,7 @@ nsHTMLEditRules::SplitAsNeeded(const nsAString *aTag,
   {
     // we found a place for block, but above inOutParent.  We need to split nodes.
     res = mHTMLEditor->SplitNodeDeep(splitNode, *inOutParent, *inOutOffset, inOutOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     *inOutParent = tagParent;
   }
   return res;
@@ -7299,7 +7299,7 @@ nsHTMLEditRules::JoinNodesSmart( nsIDOMNode *aNodeLeft,
   PRInt32 parOffset;
   nsCOMPtr<nsIDOMNode> parent, rightParent;
   res = nsEditor::GetNodeLocation(aNodeLeft, address_of(parent), &parOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   aNodeRight->GetParentNode(getter_AddRefs(rightParent));
 
   // if they don't have the same parent, first move the 'right' node 
@@ -7307,13 +7307,13 @@ nsHTMLEditRules::JoinNodesSmart( nsIDOMNode *aNodeLeft,
   if (parent != rightParent)
   {
     res = mHTMLEditor->MoveNode(aNodeRight, parent, parOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   // defaults for outParams
   *aOutMergeParent = aNodeRight;
   res = mHTMLEditor->GetLengthOfDOMNode(aNodeLeft, *((PRUint32*)aOutMergeOffset));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // separate join rules for differing blocks
   if (nsHTMLEditUtils::IsList(aNodeLeft) ||
@@ -7321,7 +7321,7 @@ nsHTMLEditRules::JoinNodesSmart( nsIDOMNode *aNodeLeft,
   {
     // for list's, merge shallow (wouldn't want to combine list items)
     res = mHTMLEditor->JoinNodes(aNodeLeft, aNodeRight, parent);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     return res;
   }
   else
@@ -7329,13 +7329,13 @@ nsHTMLEditRules::JoinNodesSmart( nsIDOMNode *aNodeLeft,
     // remember the last left child, and firt right child
     nsCOMPtr<nsIDOMNode> lastLeft, firstRight;
     res = mHTMLEditor->GetLastEditableChild(aNodeLeft, address_of(lastLeft));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = mHTMLEditor->GetFirstEditableChild(aNodeRight, address_of(firstRight));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // for list items, divs, etc, merge smart
     res = mHTMLEditor->JoinNodes(aNodeLeft, aNodeRight, parent);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     if (lastLeft && firstRight &&
         mHTMLEditor->NodesSameType(lastLeft, firstRight) &&
@@ -7368,7 +7368,7 @@ nsHTMLEditRules::GetTopEnclosingMailCite(nsIDOMNode *aNode,
     if (nsTextEditUtils::IsBody(node)) break;
     
     res = node->GetParentNode(getter_AddRefs(parentNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     node = parentNode;
   }
 
@@ -7429,11 +7429,11 @@ nsHTMLEditRules::ReapplyCachedStyles()
   // get selection point
   nsCOMPtr<nsISelection>selection;
   nsresult res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsCOMPtr<nsIDOMNode> selNode;
   PRInt32 selOffset;
   res = mHTMLEditor->GetStartNodeAndOffset(selection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   res = NS_OK;
   PRInt32 j;
@@ -7454,7 +7454,7 @@ nsHTMLEditRules::ReapplyCachedStyles()
       {
         res = mHTMLEditor->GetInlinePropertyBase(mCachedStyles[j].tag, &(mCachedStyles[j].attr), &(mCachedStyles[j].value), 
                                                         &bFirst, &bAny, &bAll, &curValue, PR_FALSE);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       // this style has disappeared through deletion.  Add it onto our typeinstate:
       if (!bAny) 
@@ -7493,9 +7493,9 @@ nsHTMLEditRules::AdjustSpecialBreaks(PRBool aSafeToAskFrames)
   nsEmptyEditableFunctor functor(mHTMLEditor);
   nsDOMIterator iter;
   nsresult res = iter.Init(mDocChangeRange);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = iter.AppendList(functor, arrayOfNodes);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // put moz-br's into these empty li's and td's
   nodeCount = arrayOfNodes.Count();
@@ -7509,9 +7509,9 @@ nsHTMLEditRules::AdjustSpecialBreaks(PRBool aSafeToAskFrames)
     nsCOMPtr<nsIDOMNode> brNode, theNode = arrayOfNodes[0];
     arrayOfNodes.RemoveObjectAt(0);
     res = nsEditor::GetLengthOfDOMNode(theNode, len);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = CreateMozBR(theNode, (PRInt32)len, address_of(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   return res;
@@ -7524,7 +7524,7 @@ nsHTMLEditRules::AdjustWhitespace(nsISelection *aSelection)
   nsCOMPtr<nsIDOMNode> selNode;
   PRInt32 selOffset;
   nsresult res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // ask whitespace object to tweak nbsp's
   return nsWSRunObject(mHTMLEditor, selNode, selOffset).AdjustWhitespace();
@@ -7536,27 +7536,27 @@ nsHTMLEditRules::PinSelectionToNewBlock(nsISelection *aSelection)
   if (!aSelection) return NS_ERROR_NULL_POINTER;
   PRBool bCollapsed;
   nsresult res = aSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!bCollapsed) return res;
 
   // get the (collapsed) selection location
   nsCOMPtr<nsIDOMNode> selNode, temp;
   PRInt32 selOffset;
   res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   temp = selNode;
   
   // use ranges and sRangeHelper to compare sel point to new block
   nsCOMPtr<nsIDOMRange> range = do_CreateInstance("@mozilla.org/content/range;1");
   res = range->SetStart(selNode, selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = range->SetEnd(selNode, selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsCOMPtr<nsIContent> block (do_QueryInterface(mNewBlock));
   if (!block) return NS_ERROR_NO_INTERFACE;
   PRBool nodeBefore, nodeAfter;
   res = mHTMLEditor->sRangeHelper->CompareNodeToRange(block, range, &nodeBefore, &nodeAfter);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   if (nodeBefore && nodeAfter)
     return NS_OK;  // selection is inside block
@@ -7569,13 +7569,13 @@ nsHTMLEditRules::PinSelectionToNewBlock(nsISelection *aSelection)
     if (mHTMLEditor->IsTextNode(tmp) || mHTMLEditor->IsContainer(tmp))
     {
       res = nsEditor::GetLengthOfDOMNode(tmp, endPoint);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     else
     {
       nsCOMPtr<nsIDOMNode> tmp2;
       res = nsEditor::GetNodeLocation(tmp, address_of(tmp2), (PRInt32*)&endPoint);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       tmp = tmp2;
       endPoint++;  // want to be after this node
     }
@@ -7591,7 +7591,7 @@ nsHTMLEditRules::PinSelectionToNewBlock(nsISelection *aSelection)
     {
       nsCOMPtr<nsIDOMNode> tmp2;
       res = nsEditor::GetNodeLocation(tmp, address_of(tmp2), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       tmp = tmp2;
     }
     return aSelection->Collapse(tmp, 0);
@@ -7608,14 +7608,14 @@ nsHTMLEditRules::CheckInterlinePosition(nsISelection *aSelection)
   // if the selection isn't collapsed, do nothing.
   PRBool bCollapsed;
   nsresult res = aSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!bCollapsed) return res;
 
   // get the (collapsed) selection location
   nsCOMPtr<nsIDOMNode> selNode, node;
   PRInt32 selOffset;
   res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // are we after a block?  If so try set caret to following content
   mHTMLEditor->GetPriorHTMLSibling(selNode, selOffset, address_of(node));
@@ -7652,14 +7652,14 @@ nsHTMLEditRules::AdjustSelection(nsISelection *aSelection, nsIEditor::EDirection
   // only a single break selected, and collapse it.  Good thing?  Beats me.
   PRBool bCollapsed;
   nsresult res = aSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!bCollapsed) return res;
 
   // get the (collapsed) selection location
   nsCOMPtr<nsIDOMNode> selNode, temp;
   PRInt32 selOffset;
   res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   temp = selNode;
   
   // are we in an editable node?
@@ -7667,7 +7667,7 @@ nsHTMLEditRules::AdjustSelection(nsISelection *aSelection, nsIEditor::EDirection
   {
     // scan up the tree until we find an editable place to be
     res = nsEditor::GetNodeLocation(temp, address_of(selNode), &selOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!selNode) return NS_ERROR_FAILURE;
     temp = selNode;
   }
@@ -7680,7 +7680,7 @@ nsHTMLEditRules::AdjustSelection(nsISelection *aSelection, nsIEditor::EDirection
   if (theblock && mHTMLEditor->IsEditable(theblock)) {
     PRBool bIsEmptyNode;
     res = mHTMLEditor->IsEmptyNode(theblock, &bIsEmptyNode, PR_FALSE, PR_FALSE);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // check if br can go into the destination node
     if (bIsEmptyNode && mHTMLEditor->CanContainTag(selNode, NS_LITERAL_STRING("br")))
     {
@@ -7713,7 +7713,7 @@ nsHTMLEditRules::AdjustSelection(nsISelection *aSelection, nsIEditor::EDirection
 
   nsCOMPtr<nsIDOMNode> nearNode;
   res = mHTMLEditor->GetPriorHTMLNode(selNode, selOffset, address_of(nearNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (nearNode) 
   {
     // is nearNode also a descendant of same block?
@@ -7732,13 +7732,13 @@ nsHTMLEditRules::AdjustSelection(nsISelection *aSelection, nsIEditor::EDirection
           // like table cells won't grow in height.
           nsCOMPtr<nsIDOMNode> brNode;
           res = CreateMozBR(selNode, selOffset, address_of(brNode));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = nsEditor::GetNodeLocation(brNode, address_of(selNode), &selOffset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           // selection stays *before* moz-br, sticking to it
           selPriv->SetInterlinePosition(PR_TRUE);
           res = aSelection->Collapse(selNode,selOffset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         else
         {
@@ -7757,14 +7757,14 @@ nsHTMLEditRules::AdjustSelection(nsISelection *aSelection, nsIEditor::EDirection
 
   // we aren't in a textnode: are we adjacent to text or a break or an image?
   res = mHTMLEditor->GetPriorHTMLNode(selNode, selOffset, address_of(nearNode), PR_TRUE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (nearNode && (nsTextEditUtils::IsBreak(nearNode)
                    || nsEditor::IsTextNode(nearNode)
                    || nsHTMLEditUtils::IsImage(nearNode)
                    || nsHTMLEditUtils::IsHR(nearNode)))
     return NS_OK; // this is a good place for the caret to be
   res = mHTMLEditor->GetNextHTMLNode(selNode, selOffset, address_of(nearNode), PR_TRUE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (nearNode && (nsTextEditUtils::IsBreak(nearNode)
                    || nsEditor::IsTextNode(nearNode)
                    || nsHTMLEditUtils::IsImage(nearNode)
@@ -7774,7 +7774,7 @@ nsHTMLEditRules::AdjustSelection(nsISelection *aSelection, nsIEditor::EDirection
   // look for a nearby text node.
   // prefer the correct direction.
   res = FindNearSelectableNode(selNode, selOffset, aAction, address_of(nearNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   if (nearNode)
   {
@@ -7791,7 +7791,7 @@ nsHTMLEditRules::AdjustSelection(nsISelection *aSelection, nsIEditor::EDirection
     else  // must be break or image
     {
       res = nsEditor::GetNodeLocation(nearNode, address_of(selNode), &selOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (aAction == nsIEditor::ePrevious) selOffset++;  // want to be beyond it if we backed up to it
       res = aSelection->Collapse(selNode, selOffset);
     }
@@ -7815,7 +7815,7 @@ nsHTMLEditRules::FindNearSelectableNode(nsIDOMNode *aSelNode,
     res = mHTMLEditor->GetPriorHTMLNode(aSelNode, aSelOffset, address_of(nearNode));
   else
     res = mHTMLEditor->GetNextHTMLNode(aSelNode, aSelOffset, address_of(nearNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   if (!nearNode) // try the other direction then
   {
@@ -7828,7 +7828,7 @@ nsHTMLEditRules::FindNearSelectableNode(nsIDOMNode *aSelNode,
       res = mHTMLEditor->GetPriorHTMLNode(aSelNode, aSelOffset, address_of(nearNode));
     else
       res = mHTMLEditor->GetNextHTMLNode(aSelNode, aSelOffset, address_of(nearNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   // scan in the right direction until we find an eligible text node,
@@ -7842,7 +7842,7 @@ nsHTMLEditRules::FindNearSelectableNode(nsIDOMNode *aSelNode,
       res = mHTMLEditor->GetPriorHTMLNode(curNode, address_of(nearNode));
     else
       res = mHTMLEditor->GetNextHTMLNode(curNode, address_of(nearNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   if (nearNode)
@@ -7850,7 +7850,7 @@ nsHTMLEditRules::FindNearSelectableNode(nsIDOMNode *aSelNode,
     // don't cross any table elements
     PRBool bInDifTblElems;
     res = InDifferentTableElements(nearNode, aSelNode, &bInDifTblElems);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (bInDifTblElems) return NS_OK;  
     
     // otherwise, ok, we have found a good spot to put the selection
@@ -7925,7 +7925,7 @@ nsHTMLEditRules::RemoveEmptyNodes()
   if (!iter) return NS_ERROR_NULL_POINTER;
   
   nsresult res = iter->Init(mDocChangeRange);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   nsTArray<nsIDOMNode*> skipList;
 
@@ -7975,7 +7975,7 @@ nsHTMLEditRules::RemoveEmptyNodes()
           // user to type into.
           PRBool bIsSelInNode;
           res = SelectionEndpointInNode(node, &bIsSelInNode);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           if (!bIsSelInNode)
           {
             bIsCandidate = PR_TRUE;
@@ -7989,7 +7989,7 @@ nsHTMLEditRules::RemoveEmptyNodes()
           res = mHTMLEditor->IsEmptyNode(node, &bIsEmptyNode, PR_TRUE, PR_TRUE);  
         else  // other nodes we require to be empty
           res = mHTMLEditor->IsEmptyNode(node, &bIsEmptyNode, PR_FALSE, PR_TRUE);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (bIsEmptyNode)
         {
           if (bIsMailCite)  // mailcites go on a separate list from other empty nodes
@@ -8034,7 +8034,7 @@ nsHTMLEditRules::RemoveEmptyNodes()
     arrayOfEmptyCites.RemoveObjectAt(0);
     PRBool bIsEmptyNode;
     res = mHTMLEditor->IsEmptyNode(delNode, &bIsEmptyNode, PR_FALSE, PR_TRUE);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!bIsEmptyNode)
     {
       // we are deleting a cite that has just a br.  We want to delete cite, 
@@ -8042,12 +8042,12 @@ nsHTMLEditRules::RemoveEmptyNodes()
       nsCOMPtr<nsIDOMNode> parent, brNode;
       PRInt32 offset;
       res = nsEditor::GetNodeLocation(delNode, address_of(parent), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mHTMLEditor->CreateBR(parent, offset, address_of(brNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     res = mHTMLEditor->DeleteNode(delNode);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   return res;
@@ -8062,19 +8062,19 @@ nsHTMLEditRules::SelectionEndpointInNode(nsIDOMNode *aNode, PRBool *aResult)
   
   nsCOMPtr<nsISelection>selection;
   nsresult res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsCOMPtr<nsISelectionPrivate>selPriv(do_QueryInterface(selection));
   
   nsCOMPtr<nsIEnumerator> enumerator;
   res = selPriv->GetEnumerator(getter_AddRefs(enumerator));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!enumerator) return NS_ERROR_UNEXPECTED;
 
   for (enumerator->First(); NS_OK!=enumerator->IsDone(); enumerator->Next())
   {
     nsCOMPtr<nsISupports> currentItem;
     res = enumerator->CurrentItem(getter_AddRefs(currentItem));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!currentItem) return NS_ERROR_UNEXPECTED;
 
     nsCOMPtr<nsIDOMRange> range( do_QueryInterface(currentItem) );
@@ -8175,7 +8175,7 @@ nsHTMLEditRules::PopListItem(nsIDOMNode *aListItem, PRBool *aOutOfList)
   nsCOMPtr<nsIDOMNode> curNode( do_QueryInterface(aListItem));
   PRInt32 offset;
   nsresult res = nsEditor::GetNodeLocation(curNode, address_of(curParent), &offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
     
   if (!nsHTMLEditUtils::IsListItem(curNode))
     return NS_ERROR_FAILURE;
@@ -8185,35 +8185,35 @@ nsHTMLEditRules::PopListItem(nsIDOMNode *aListItem, PRBool *aOutOfList)
   nsCOMPtr<nsIDOMNode> curParPar;
   PRInt32 parOffset;
   res = nsEditor::GetNodeLocation(curParent, address_of(curParPar), &parOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   PRBool bIsFirstListItem;
   res = mHTMLEditor->IsFirstEditableChild(curNode, &bIsFirstListItem);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   PRBool bIsLastListItem;
   res = mHTMLEditor->IsLastEditableChild(curNode, &bIsLastListItem);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
     
   if (!bIsFirstListItem && !bIsLastListItem)
   {
     // split the list
     nsCOMPtr<nsIDOMNode> newBlock;
     res = mHTMLEditor->SplitNode(curParent, offset, getter_AddRefs(newBlock));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   if (!bIsFirstListItem) parOffset++;
   
   res = mHTMLEditor->MoveNode(curNode, curParPar, parOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
     
   // unwrap list item contents if they are no longer in a list
   if (!nsHTMLEditUtils::IsList(curParPar)
       && nsHTMLEditUtils::IsListItem(curNode)) 
   {
     res = mHTMLEditor->RemoveBlockContainer(curNode);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     *aOutOfList = PR_TRUE;
   }
   return res;
@@ -8237,25 +8237,25 @@ nsHTMLEditRules::RemoveListStructure(nsIDOMNode *aList)
       do
       {
         res = PopListItem(child, &bOutOfList);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       } while (!bOutOfList);   // keep popping it out until it's not in a list anymore
     }
     else if (nsHTMLEditUtils::IsList(child))
     {
       res = RemoveListStructure(child);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     else
     {
       // delete any non- list items for now
       res = mHTMLEditor->DeleteNode(child);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     aList->GetFirstChild(getter_AddRefs(child));
   }
   // delete the now-empty list
   res = mHTMLEditor->RemoveBlockContainer(aList);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   return res;
 }
@@ -8273,13 +8273,13 @@ nsHTMLEditRules::ConfirmSelectionInBody()
   // get the selection
   nsCOMPtr<nsISelection>selection;
   res = mHTMLEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // get the selection start location
   nsCOMPtr<nsIDOMNode> selNode, temp, parent;
   PRInt32 selOffset;
   res = mHTMLEditor->GetStartNodeAndOffset(selection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   temp = selNode;
   
   // check that selNode is inside body
@@ -8299,7 +8299,7 @@ nsHTMLEditRules::ConfirmSelectionInBody()
   
   // get the selection end location
   res = mHTMLEditor->GetEndNodeAndOffset(selection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   temp = selNode;
   
   // check that selNode is inside body
@@ -8332,7 +8332,7 @@ nsHTMLEditRules::UpdateDocChangeRange(nsIDOMRange *aRange)
   // before placing it in it's list)
   nsCOMPtr<nsIDOMNode> startNode;
   res = aRange->GetStartContainer(getter_AddRefs(startNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!mHTMLEditor->IsDescendantOfBody(startNode))
   {
     // just return - we don't need to adjust mDocChangeRange in this case
@@ -8359,29 +8359,29 @@ nsHTMLEditRules::UpdateDocChangeRange(nsIDOMRange *aRange)
       result = 1;
       res = NS_OK;
     }
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (result > 0)  // positive result means mDocChangeRange start is after aRange start
     {
       PRInt32 startOffset;
       res = aRange->GetStartOffset(&startOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mDocChangeRange->SetStart(startNode, startOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     
     // compare ends of ranges
     res = mDocChangeRange->CompareBoundaryPoints(nsIDOMRange::END_TO_END, aRange, &result);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (result < 0)  // negative result means mDocChangeRange end is before aRange end
     {
       nsCOMPtr<nsIDOMNode> endNode;
       PRInt32 endOffset;
       res = aRange->GetEndContainer(getter_AddRefs(endNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = aRange->GetEndOffset(&endOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = mDocChangeRange->SetEnd(endNode, endOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   return res;
@@ -8396,7 +8396,7 @@ nsHTMLEditRules::InsertMozBRIfNeeded(nsIDOMNode *aNode)
   PRBool isEmpty;
   nsCOMPtr<nsIDOMNode> brNode;
   nsresult res = mHTMLEditor->IsEmptyNode(aNode, &isEmpty);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (isEmpty)
   {
     res = CreateMozBR(aNode, 0, address_of(brNode));
@@ -8426,7 +8426,7 @@ nsHTMLEditRules::DidCreateNode(const nsAString& aTag,
   if (!mListenerEnabled) return NS_OK;
   // assumption that Join keeps the righthand node
   nsresult res = mUtilRange->SelectNode(aNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = UpdateDocChangeRange(mUtilRange);
   return res;  
 }
@@ -8447,7 +8447,7 @@ nsHTMLEditRules::DidInsertNode(nsIDOMNode *aNode,
 {
   if (!mListenerEnabled) return NS_OK;
   nsresult res = mUtilRange->SelectNode(aNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = UpdateDocChangeRange(mUtilRange);
   return res;  
 }
@@ -8458,7 +8458,7 @@ nsHTMLEditRules::WillDeleteNode(nsIDOMNode *aChild)
 {
   if (!mListenerEnabled) return NS_OK;
   nsresult res = mUtilRange->SelectNode(aChild);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = UpdateDocChangeRange(mUtilRange);
   return res;  
 }
@@ -8486,9 +8486,9 @@ nsHTMLEditRules::DidSplitNode(nsIDOMNode *aExistingRightNode,
 {
   if (!mListenerEnabled) return NS_OK;
   nsresult res = mUtilRange->SetStart(aNewLeftNode, 0);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = mUtilRange->SetEnd(aExistingRightNode, 0);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = UpdateDocChangeRange(mUtilRange);
   return res;  
 }
@@ -8513,9 +8513,9 @@ nsHTMLEditRules::DidJoinNodes(nsIDOMNode  *aLeftNode,
   if (!mListenerEnabled) return NS_OK;
   // assumption that Join keeps the righthand node
   nsresult res = mUtilRange->SetStart(aRightNode, mJoinOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = mUtilRange->SetEnd(aRightNode, mJoinOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = UpdateDocChangeRange(mUtilRange);
   return res;  
 }
@@ -8538,9 +8538,9 @@ nsHTMLEditRules::DidInsertText(nsIDOMCharacterData *aTextNode,
   PRInt32 length = aString.Length();
   nsCOMPtr<nsIDOMNode> theNode = do_QueryInterface(aTextNode);
   nsresult res = mUtilRange->SetStart(theNode, aOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = mUtilRange->SetEnd(theNode, aOffset+length);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = UpdateDocChangeRange(mUtilRange);
   return res;  
 }
@@ -8562,9 +8562,9 @@ nsHTMLEditRules::DidDeleteText(nsIDOMCharacterData *aTextNode,
   if (!mListenerEnabled) return NS_OK;
   nsCOMPtr<nsIDOMNode> theNode = do_QueryInterface(aTextNode);
   nsresult res = mUtilRange->SetStart(theNode, aOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = mUtilRange->SetEnd(theNode, aOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = UpdateDocChangeRange(mUtilRange);
   return res;  
 }
@@ -8592,13 +8592,13 @@ nsHTMLEditRules::WillDeleteSelection(nsISelection *aSelection)
   PRInt32 selOffset;
 
   nsresult res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = mUtilRange->SetStart(selNode, selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = mHTMLEditor->GetEndNodeAndOffset(aSelection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = mUtilRange->SetEnd(selNode, selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = UpdateDocChangeRange(mUtilRange);
   return res;  
 }
@@ -8641,7 +8641,7 @@ nsHTMLEditRules::RemoveAlignment(nsIDOMNode * aNode, const nsAString & aAlignTyp
     }
     PRBool isBlock;
     res = mHTMLEditor->NodeIsBlockStatic(child, &isBlock);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     if ((isBlock && !nsHTMLEditUtils::IsDiv(child)) || nsHTMLEditUtils::IsHR(child))
     {
@@ -8651,7 +8651,7 @@ nsHTMLEditRules::RemoveAlignment(nsIDOMNode * aNode, const nsAString & aAlignTyp
       {
         // remove the ALIGN attribute if this element can have it
         res = mHTMLEditor->RemoveAttribute(curElem, NS_LITERAL_STRING("align"));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       if (useCSS)
       {
@@ -8664,13 +8664,13 @@ nsHTMLEditRules::RemoveAlignment(nsIDOMNode * aNode, const nsAString & aAlignTyp
           nsAutoString dummyCssValue;
           res = mHTMLEditor->mHTMLCSSUtils->RemoveCSSInlineStyle(child, nsEditProperty::cssTextAlign, dummyCssValue);
         }
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       if (!nsHTMLEditUtils::IsTable(child))
       {
         // unless this is a table, look at children
         res = RemoveAlignment(child, aAlignType, PR_TRUE);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     else if (nsEditor::NodeIsType(child, nsEditProperty::center)
@@ -8679,7 +8679,7 @@ nsHTMLEditRules::RemoveAlignment(nsIDOMNode * aNode, const nsAString & aAlignTyp
       // this is a CENTER or a DIV element and we have to remove it
       // first remove children's alignment
       res = RemoveAlignment(child, aAlignType, PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       if (useCSS && nsHTMLEditUtils::IsDiv(child))
       {
@@ -8687,19 +8687,19 @@ nsHTMLEditRules::RemoveAlignment(nsIDOMNode * aNode, const nsAString & aAlignTyp
         // if it does not carry any style hint (style attr, class or ID)
         nsAutoString dummyCssValue;
         res = mHTMLEditor->mHTMLCSSUtils->RemoveCSSInlineStyle(child, nsEditProperty::cssTextAlign, dummyCssValue);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         nsCOMPtr<nsIDOMElement> childElt = do_QueryInterface(child);
         PRBool hasStyleOrIdOrClass;
         res = mHTMLEditor->HasStyleOrIdOrClass(childElt, &hasStyleOrIdOrClass);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (!hasStyleOrIdOrClass)
         {
           // we may have to insert BRs in first and last position of DIV's children
           // if the nodes before/after are not blocks and not BRs
           res = MakeSureElemStartsOrEndsOnCR(child);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = mHTMLEditor->RemoveContainer(child);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
       }
       else
@@ -8707,11 +8707,11 @@ nsHTMLEditRules::RemoveAlignment(nsIDOMNode * aNode, const nsAString & aAlignTyp
         // we may have to insert BRs in first and last position of element's children
         // if the nodes before/after are not blocks and not BRs
         res = MakeSureElemStartsOrEndsOnCR(child);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
 
         // in HTML mode, let's remove the element
         res = mHTMLEditor->RemoveContainer(child);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     child = tmp;
@@ -8737,11 +8737,11 @@ nsHTMLEditRules::MakeSureElemStartsOrEndsOnCR(nsIDOMNode *aNode, PRBool aStarts)
   {
     res = mHTMLEditor->GetLastEditableChild(aNode, address_of(child));
   }
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!child) return NS_OK;
   PRBool isChildBlock;
   res = mHTMLEditor->NodeIsBlockStatic(child, &isChildBlock);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   PRBool foundCR = PR_FALSE;
   if (isChildBlock || nsTextEditUtils::IsBreak(child))
   {
@@ -8758,12 +8758,12 @@ nsHTMLEditRules::MakeSureElemStartsOrEndsOnCR(nsIDOMNode *aNode, PRBool aStarts)
     {
       res = mHTMLEditor->GetNextHTMLSibling(aNode, address_of(sibling));
     }
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (sibling)
     {
       PRBool isBlock;
       res = mHTMLEditor->NodeIsBlockStatic(sibling, &isBlock);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (isBlock || nsTextEditUtils::IsBreak(sibling))
       {
         foundCR = PR_TRUE;
@@ -8782,15 +8782,15 @@ nsHTMLEditRules::MakeSureElemStartsOrEndsOnCR(nsIDOMNode *aNode, PRBool aStarts)
     {
       nsCOMPtr<nsIDOMNodeList> childNodes;
       res = aNode->GetChildNodes(getter_AddRefs(childNodes));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!childNodes) return NS_ERROR_NULL_POINTER;
       PRUint32 childCount;
       res = childNodes->GetLength(&childCount);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       offset = childCount;
     }
     res = mHTMLEditor->CreateBR(aNode, offset, address_of(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return NS_OK;
 }
@@ -8799,7 +8799,7 @@ NS_IMETHODIMP
 nsHTMLEditRules::MakeSureElemStartsOrEndsOnCR(nsIDOMNode *aNode)
 {
   nsresult res = MakeSureElemStartsOrEndsOnCR(aNode, PR_FALSE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = MakeSureElemStartsOrEndsOnCR(aNode, PR_TRUE);
   return res;
 }
@@ -8817,7 +8817,7 @@ nsHTMLEditRules::AlignBlock(nsIDOMElement * aElement, const nsAString * aAlignTy
   }
 
   nsresult res = RemoveAlignment(node, *aAlignType, aContentsOnly);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   NS_NAMED_LITERAL_STRING(attr, "align");
   PRBool useCSS;
   mHTMLEditor->GetIsCSSEnabled(&useCSS);
@@ -8825,14 +8825,14 @@ nsHTMLEditRules::AlignBlock(nsIDOMElement * aElement, const nsAString * aAlignTy
     // let's use CSS alignment; we use margin-left and margin-right for tables
     // and text-align for other block-level elements
     res = mHTMLEditor->SetAttributeOrEquivalent(aElement, attr, *aAlignType, PR_FALSE); 
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   else {
     // HTML case; this code is supposed to be called ONLY if the element
     // supports the align attribute but we'll never know...
     if (nsHTMLEditUtils::SupportsAlignAttr(node)) {
       res = mHTMLEditor->SetAttribute(aElement, attr, *aAlignType);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   return NS_OK;
@@ -8898,13 +8898,13 @@ nsHTMLEditRules::RelativeChangeIndentationOfElementNode(nsIDOMNode *aNode, PRInt
         // we deal with a DIV ; let's see if it is useless and if we can remove it
         nsCOMPtr<nsIDOMNamedNodeMap> attributeList;
         res = element->GetAttributes(getter_AddRefs(attributeList));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         PRUint32 count;
         attributeList->GetLength(&count);
         if (!count) {
           // the DIV has no attribute at all, let's remove it
           res = mHTMLEditor->RemoveContainer(element);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         else if (1 == count) {
           nsCOMPtr<nsIDOMNode> styleAttributeNode;
@@ -8912,7 +8912,7 @@ nsHTMLEditRules::RelativeChangeIndentationOfElementNode(nsIDOMNode *aNode, PRInt
                                             getter_AddRefs(styleAttributeNode));
           if (!styleAttributeNode) {
             res = mHTMLEditor->RemoveContainer(element);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
         }
       }
@@ -8930,7 +8930,7 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
 {
   if (!aSelection || !aCancel || !aHandled) { return NS_ERROR_NULL_POINTER; }
   nsresult res = WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // initialize out param
   // we want to ignore result of WillInsert()
@@ -8948,7 +8948,7 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
   }
 
   res = NormalizeSelection(aSelection);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsAutoSelectionReset selectionResetter(aSelection, mHTMLEditor);
   
   // convert the selection ranges into "promoted" selection ranges:
@@ -8958,12 +8958,12 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
   
   nsCOMArray<nsIDOMRange> arrayOfRanges;
   res = GetPromotedRanges(aSelection, arrayOfRanges, kSetAbsolutePosition);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // use these ranges to contruct a list of nodes to act on.
   nsCOMArray<nsIDOMNode> arrayOfNodes;
   res = GetNodesForOperation(arrayOfRanges, arrayOfNodes, kSetAbsolutePosition);
-  if (NS_FAILED(res)) return res;                                 
+  NS_ENSURE_SUCCESS(res, res);                                 
                                      
   NS_NAMED_LITERAL_STRING(divType, "div");
 
@@ -8976,12 +8976,12 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
     
     // get selection location
     res = mHTMLEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // make sure we can put a block here
     res = SplitAsNeeded(&divType, address_of(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = mHTMLEditor->CreateNode(divType, parent, offset, getter_AddRefs(thePositionedDiv));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // remember our new block for postprocessing
     mNewBlock = thePositionedDiv;
     // delete anything that was in the list of nodes
@@ -8989,9 +8989,9 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
     {
       nsCOMPtr<nsIDOMNode> curNode = arrayOfNodes[0];
       res = mHTMLEditor->DeleteNode(curNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = arrayOfNodes.RemoveObjectAt(0);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     // put selection in new block
     res = aSelection->Collapse(thePositionedDiv,0);
@@ -9015,7 +9015,7 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
 
     PRInt32 offset;
     res = nsEditor::GetNodeLocation(curNode, address_of(curParent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
      
     // some logic for putting list items into nested lists...
     if (nsHTMLEditUtils::IsList(curParent))
@@ -9035,7 +9035,7 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
         ToLowerCase(listTag);
         // create a new nested list of correct type
         res = SplitAsNeeded(&listTag, address_of(curParent), &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (!curPositionedDiv) {
           PRInt32 parentOffset;
           nsCOMPtr<nsIDOMNode> curParentParent;
@@ -9044,14 +9044,14 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
           mNewBlock = curPositionedDiv;
         }
         res = mHTMLEditor->CreateNode(listTag, curPositionedDiv, -1, getter_AddRefs(curList));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // curList is now the correct thing to put curNode in
         // remember our new block for postprocessing
         // mNewBlock = curList;
       }
       // tuck the node into the end of the active list
       res = mHTMLEditor->MoveNode(curNode, curList, -1);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // forget curPositionedDiv, if any
       // curPositionedDiv = nsnull;
     }
@@ -9069,7 +9069,7 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
       {
         if (indentedLI == listitem) continue;  // already indented this list item
         res = nsEditor::GetNodeLocation(listitem, address_of(curParent), &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // check to see if curList is still appropriate.  Which it is if
         // curNode is still right after it in the same list.
         if (curList)
@@ -9085,7 +9085,7 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
           ToLowerCase(listTag);
           // create a new nested list of correct type
           res = SplitAsNeeded(&listTag, address_of(curParent), &offset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           if (!curPositionedDiv) {
           PRInt32 parentOffset;
           nsCOMPtr<nsIDOMNode> curParentParent;
@@ -9094,10 +9094,10 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
             mNewBlock = curPositionedDiv;
           }
           res = mHTMLEditor->CreateNode(listTag, curPositionedDiv, -1, getter_AddRefs(curList));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         res = mHTMLEditor->MoveNode(listitem, curList, -1);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // remember we indented this li
         indentedLI = listitem;
       }
@@ -9116,9 +9116,9 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
             continue;
           }
           res = SplitAsNeeded(&divType, address_of(curParent), &offset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = mHTMLEditor->CreateNode(divType, curParent, offset, getter_AddRefs(curPositionedDiv));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           // remember our new block for postprocessing
           mNewBlock = curPositionedDiv;
           // curPositionedDiv is now the correct thing to put curNode in
@@ -9126,7 +9126,7 @@ nsHTMLEditRules::WillAbsolutePosition(nsISelection *aSelection, PRBool *aCancel,
           
         // tuck the node into the end of the active blockquote
         res = mHTMLEditor->MoveNode(curNode, curPositionedDiv, -1);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // forget curList, if any
         curList = nsnull;
       }
@@ -9148,7 +9148,7 @@ nsHTMLEditRules::WillRemoveAbsolutePosition(nsISelection *aSelection, PRBool *aC
 {
   if (!aSelection || !aCancel || !aHandled) { return NS_ERROR_NULL_POINTER; }
   nsresult res = WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // initialize out param
   // we want to ignore aCancel from WillInsert()
@@ -9157,7 +9157,7 @@ nsHTMLEditRules::WillRemoveAbsolutePosition(nsISelection *aSelection, PRBool *aC
 
   nsCOMPtr<nsIDOMElement>  elt;
   res = mHTMLEditor->GetAbsolutelyPositionedSelectionContainer(getter_AddRefs(elt));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsAutoSelectionReset selectionResetter(aSelection, mHTMLEditor);
 
@@ -9173,7 +9173,7 @@ nsHTMLEditRules::WillRelativeChangeZIndex(nsISelection *aSelection,
 {
   if (!aSelection || !aCancel || !aHandled) { return NS_ERROR_NULL_POINTER; }
   nsresult res = WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // initialize out param
   // we want to ignore aCancel from WillInsert()
@@ -9182,7 +9182,7 @@ nsHTMLEditRules::WillRelativeChangeZIndex(nsISelection *aSelection,
 
   nsCOMPtr<nsIDOMElement>  elt;
   res = mHTMLEditor->GetAbsolutelyPositionedSelectionContainer(getter_AddRefs(elt));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsAutoSelectionReset selectionResetter(aSelection, mHTMLEditor);
 
diff --git a/editor/libeditor/html/nsHTMLEditor.cpp b/editor/libeditor/html/nsHTMLEditor.cpp
index 9b0ba33cf92..3a675a56c1f 100644
--- a/editor/libeditor/html/nsHTMLEditor.cpp
+++ b/editor/libeditor/html/nsHTMLEditor.cpp
@@ -335,7 +335,7 @@ nsHTMLEditor::Init(nsIDOMDocument *aDoc, nsIPresShell *aPresShell,
     }
   }
 
-  if (NS_FAILED(rulesRes)) return rulesRes;
+  NS_ENSURE_SUCCESS(rulesRes, rulesRes);
   return result;
 }
 
@@ -521,7 +521,7 @@ nsHTMLEditor::InitRules()
 {
   // instantiate the rules for the html editor
   nsresult res = NS_NewHTMLEditRules(getter_AddRefs(mRules));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!mRules) return NS_ERROR_UNEXPECTED;
   res = mRules->Init(static_cast<nsPlaintextEditor*>(this));
   
@@ -567,7 +567,7 @@ nsHTMLEditor::BeginningOfDocument()
              (visType==nsWSRunObject::eSpecial))
     {
       res = GetNodeLocation(visNode, address_of(selNode), &selOffset);
-      if (NS_FAILED(res)) return res; 
+      NS_ENSURE_SUCCESS(res, res); 
       done = PR_TRUE;
     }
     else if (visType==nsWSRunObject::eOtherBlock)
@@ -588,7 +588,7 @@ nsHTMLEditor::BeginningOfDocument()
         // We want to place the caret in front of that block.
 
         res = GetNodeLocation(visNode, address_of(selNode), &selOffset);
-        if (NS_FAILED(res)) return res; 
+        NS_ENSURE_SUCCESS(res, res); 
         done = PR_TRUE;
       }
       else
@@ -599,7 +599,7 @@ nsHTMLEditor::BeginningOfDocument()
         {
           // skip the empty block
           res = GetNodeLocation(visNode, address_of(curNode), &curOffset);
-          if (NS_FAILED(res)) return res; 
+          NS_ENSURE_SUCCESS(res, res); 
           ++curOffset;
         }
         else
@@ -827,7 +827,7 @@ nsHTMLEditor::NodeIsBlockStatic(nsIDOMNode *aNode, PRBool *aIsBlock)
 
       nsAutoString tagName;
       rv = element->GetTagName(tagName);
-      if (NS_FAILED(rv)) return rv;
+      NS_ENSURE_SUCCESS(rv, rv);
 
       assertmsg.Append(tagName);
       char* assertstr = ToNewCString(assertmsg);
@@ -1459,7 +1459,7 @@ NS_IMETHODIMP nsHTMLEditor::TabInTable(PRBool inIsShift, PRBool *outHandled)
   nsCOMPtr<nsIDOMElement> cellElement;
     // can't use |NS_LITERAL_STRING| here until |GetElementOrParentByTagName| is fixed to accept readables
   nsresult res = GetElementOrParentByTagName(NS_LITERAL_STRING("td"), nsnull, getter_AddRefs(cellElement));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // Do nothing -- we didn't find a table cell
   if (!cellElement) return NS_OK;
 
@@ -1471,15 +1471,15 @@ NS_IMETHODIMP nsHTMLEditor::TabInTable(PRBool inIsShift, PRBool *outHandled)
   // first create an iterator over the table
   nsCOMPtr<nsIContentIterator> iter =
       do_CreateInstance("@mozilla.org/content/post-content-iterator;1", &res);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!iter) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsIContent> cTbl = do_QueryInterface(tbl);
   nsCOMPtr<nsIContent> cBlock = do_QueryInterface(cellElement);
   res = iter->Init(cTbl);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // position iter at block
   res = iter->PositionAt(cBlock);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMNode> node;
   do
@@ -1495,7 +1495,7 @@ NS_IMETHODIMP nsHTMLEditor::TabInTable(PRBool inIsShift, PRBool *outHandled)
         GetEnclosingTable(node) == tbl)
     {
       res = CollapseSelectionToDeepestNonTableFirstChild(nsnull, node);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       *outHandled = PR_TRUE;
       return NS_OK;
     }
@@ -1506,7 +1506,7 @@ NS_IMETHODIMP nsHTMLEditor::TabInTable(PRBool inIsShift, PRBool *outHandled)
     // if we havent handled it yet then we must have run off the end of
     // the table.  Insert a new row.
     res = InsertTableRow(1, PR_TRUE);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     *outHandled = PR_TRUE;
     // put selection in right place
     // Use table code to get selection and index to new row...
@@ -1519,10 +1519,10 @@ NS_IMETHODIMP nsHTMLEditor::TabInTable(PRBool inIsShift, PRBool *outHandled)
                          getter_AddRefs(cell), 
                          nsnull, nsnull,
                          &row, nsnull);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // ...so that we can ask for first cell in that row...
     res = GetCellAt(tblElement, row, 0, getter_AddRefs(cell));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // ...and then set selection there.
     // (Note that normally you should use CollapseSelectionToDeepestNonTableFirstChild(),
     //  but we know cell is an empty new cell, so this works fine)
@@ -1570,20 +1570,20 @@ NS_IMETHODIMP nsHTMLEditor::CreateBRImpl(nsCOMPtr<nsIDOMNode> *aInOutParent,
     {
       // split the text node
       res = SplitNode(node, theOffset, getter_AddRefs(tmp));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = GetNodeLocation(node, address_of(tmp), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     // create br
     res = CreateNode(brType, tmp, offset, getter_AddRefs(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     *aInOutParent = tmp;
     *aInOutOffset = offset+1;
   }
   else
   {
     res = CreateNode(brType, node, theOffset, getter_AddRefs(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     (*aInOutOffset)++;
   }
 
@@ -1594,10 +1594,10 @@ NS_IMETHODIMP nsHTMLEditor::CreateBRImpl(nsCOMPtr<nsIDOMNode> *aInOutParent,
     nsCOMPtr<nsIDOMNode> parent;
     PRInt32 offset;
     res = GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));
     res = GetNodeLocation(*outBRNode, address_of(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (aSelect == eNext)
     {
       // position selection after br
@@ -1634,26 +1634,26 @@ NS_IMETHODIMP nsHTMLEditor::InsertBR(nsCOMPtr<nsIDOMNode> *outBRNode)
   nsAutoRules beginRulesSniffing(this, kOpInsertText, nsIEditor::eNext);
 
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));
   res = selection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!bCollapsed)
   {
     res = DeleteSelection(nsIEditor::eNone);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   nsCOMPtr<nsIDOMNode> selNode;
   PRInt32 selOffset;
   res = GetStartNodeAndOffset(selection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   res = CreateBR(selNode, selOffset, outBRNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
     
   // position selection after br
   res = GetNodeLocation(*outBRNode, address_of(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   selPriv->SetInterlinePosition(PR_TRUE);
   res = selection->Collapse(selNode, selOffset+1);
   
@@ -1672,7 +1672,7 @@ nsHTMLEditor::CollapseSelectionToDeepestNonTableFirstChild(nsISelection *aSelect
     selection = aSelection;
   } else {
     res = GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!selection) return NS_ERROR_FAILURE;
   }
   nsCOMPtr<nsIDOMNode> node = aNode;
@@ -1707,7 +1707,7 @@ nsHTMLEditor::ReplaceHeadContentsWithHTML(const nsAString& aSourceToInsert)
   nsAutoRules beginRulesSniffing(this, kOpIgnore, nsIEditor::eNone); // don't do any post processing, rules get confused
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   ForceCompositionEnd();
@@ -1719,7 +1719,7 @@ nsHTMLEditor::ReplaceHeadContentsWithHTML(const nsAString& aSourceToInsert)
 
   nsCOMPtr<nsIDOMNodeList>nodeList; 
   res = doc->GetElementsByTagName(NS_LITERAL_STRING("head"), getter_AddRefs(nodeList));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!nodeList) return NS_ERROR_NULL_POINTER;
 
   PRUint32 count; 
@@ -1728,7 +1728,7 @@ nsHTMLEditor::ReplaceHeadContentsWithHTML(const nsAString& aSourceToInsert)
 
   nsCOMPtr<nsIDOMNode> headNode;
   res = nodeList->Item(0, getter_AddRefs(headNode)); 
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!headNode) return NS_ERROR_NULL_POINTER;
 
   // First, make sure there are no return chars in the source.
@@ -1747,7 +1747,7 @@ nsHTMLEditor::ReplaceHeadContentsWithHTML(const nsAString& aSourceToInsert)
   nsAutoEditBatch beginBatching(this);
 
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   // Get the first range in the selection, for context:
@@ -1780,11 +1780,11 @@ nsHTMLEditor::ReplaceHeadContentsWithHTML(const nsAString& aSourceToInsert)
   // First delete all children in head
   do {
     res = headNode->GetFirstChild(getter_AddRefs(child));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (child)
     {
       res = DeleteNode(child);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   } while (child);
 
@@ -1795,11 +1795,11 @@ nsHTMLEditor::ReplaceHeadContentsWithHTML(const nsAString& aSourceToInsert)
   // Loop over the contents of the fragment and move into the document
   do {
     res = fragmentAsNode->GetFirstChild(getter_AddRefs(child));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (child)
     {
       res = InsertNode(child, headNode, offsetOfNewNode++);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   } while (child);
 
@@ -1813,10 +1813,10 @@ nsHTMLEditor::RebuildDocumentFromSource(const nsAString& aSourceString)
 
   nsCOMPtr<nsISelection>selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsIDOMElement *bodyElement = GetRoot();
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!bodyElement) return NS_ERROR_NULL_POINTER;
 
   // Find where the <body> tag starts.
@@ -1873,10 +1873,10 @@ nsHTMLEditor::RebuildDocumentFromSource(const nsAString& aSourceString)
       // so we assume that there is no head
       res = ReplaceHeadContentsWithHTML(head);
   }
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   res = SelectAll();
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   if (!foundbody) {
     NS_NAMED_LITERAL_STRING(body, "<body>");
@@ -1904,7 +1904,7 @@ nsHTMLEditor::RebuildDocumentFromSource(const nsAString& aSourceString)
   }
 
   res = LoadHTML(Substring(beginbody, endtotal));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // Now we must copy attributes user might have edited on the <body> tag
   //  because InsertHTML (actually, CreateContextualFragment()) 
@@ -1925,26 +1925,26 @@ nsHTMLEditor::RebuildDocumentFromSource(const nsAString& aSourceString)
 
   nsCOMPtr<nsIDOMRange> range;
   res = selection->GetRangeAt(0, getter_AddRefs(range));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMNSRange> nsrange (do_QueryInterface(range));
   if (!nsrange) return NS_ERROR_NO_INTERFACE;
 
   nsCOMPtr<nsIDOMDocumentFragment> docfrag;
   res = nsrange->CreateContextualFragment(bodyTag, getter_AddRefs(docfrag));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMNode> fragmentAsNode (do_QueryInterface(docfrag));
   if (!fragmentAsNode) return NS_ERROR_NULL_POINTER;
   
   nsCOMPtr<nsIDOMNode> child;
   res = fragmentAsNode->GetFirstChild(getter_AddRefs(child));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!child) return NS_ERROR_NULL_POINTER;
   
   // Copy all attributes from the div child to current body element
   res = CloneAttributes(bodyElement, child);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // place selection at first editable content
   return BeginningOfDocument();
@@ -2103,19 +2103,19 @@ nsHTMLEditor::InsertElementAtSelection(nsIDOMElement* aElement, PRBool aDeleteSe
       if (!SetCaretInTableCell(aElement))
       {
         res = SetCaretAfterElement(aElement);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       // check for inserting a whole table at the end of a block. If so insert a br after it.
       if (nsHTMLEditUtils::IsTable(node))
       {
         PRBool isLast;
         res = IsLastEditableChild(node, &isLast);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (isLast)
         {
           nsCOMPtr<nsIDOMNode> brNode;
           res = CreateBR(parentSelectedNode, offsetForInsert+1, address_of(brNode));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           selection->Collapse(parentSelectedNode, offsetForInsert+1);
         }
       }
@@ -2196,7 +2196,7 @@ nsHTMLEditor::SelectElement(nsIDOMElement* aElement)
   {
     nsCOMPtr<nsISelection> selection;
     res = GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!selection) return NS_ERROR_NULL_POINTER;
     nsCOMPtr<nsIDOMNode>parent;
     res = aElement->GetParentNode(getter_AddRefs(parent));
@@ -2229,11 +2229,11 @@ nsHTMLEditor::SetCaretAfterElement(nsIDOMElement* aElement)
   {
     nsCOMPtr<nsISelection> selection;
     res = GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!selection) return NS_ERROR_NULL_POINTER;
     nsCOMPtr<nsIDOMNode>parent;
     res = aElement->GetParentNode(getter_AddRefs(parent));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!parent) return NS_ERROR_NULL_POINTER;
     PRInt32 offsetInParent;
     res = GetChildOffset(aElement, parent, offsetInParent);
@@ -2327,19 +2327,19 @@ nsHTMLEditor::GetCSSBackgroundColorState(PRBool *aMixed, nsAString &aOutColor, P
   // get selection
   nsCOMPtr<nsISelection>selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // get selection location
   nsCOMPtr<nsIDOMNode> parent;
   PRInt32 offset;
   res = GetStartNodeAndOffset(selection, getter_AddRefs(parent), &offset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!parent) return NS_ERROR_NULL_POINTER;
 
   // is the selection collapsed?
   PRBool bCollapsed;
   res = selection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsCOMPtr<nsIDOMNode> nodeToExamine;
   if (bCollapsed || IsTextNode(parent))
   {
@@ -2359,7 +2359,7 @@ nsHTMLEditor::GetCSSBackgroundColorState(PRBool *aMixed, nsAString &aOutColor, P
   // is the node to examine a block ?
   PRBool isBlock;
   res = NodeIsBlockStatic(nodeToExamine, &isBlock);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMNode> tmp;
 
@@ -2398,13 +2398,13 @@ nsHTMLEditor::GetCSSBackgroundColorState(PRBool *aMixed, nsAString &aOutColor, P
     if (IsTextNode(nodeToExamine)) {
       // if the node of interest is a text node, let's climb a level
       res = nodeToExamine->GetParentNode(getter_AddRefs(parent));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       nodeToExamine = parent;
     }
     do {
       // is the node to examine a block ?
       res = NodeIsBlockStatic(nodeToExamine, &isBlock);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (isBlock) {
         // yes it is a block; in that case, the text background color is transparent
         aOutColor.AssignLiteral("transparent");
@@ -2421,7 +2421,7 @@ nsHTMLEditor::GetCSSBackgroundColorState(PRBool *aMixed, nsAString &aOutColor, P
       }
       tmp.swap(nodeToExamine);
       res = tmp->GetParentNode(getter_AddRefs(nodeToExamine));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     } while ( aOutColor.EqualsLiteral("transparent") && nodeToExamine );
   }
   return NS_OK;
@@ -2441,7 +2441,7 @@ nsHTMLEditor::GetHTMLBackgroundColorState(PRBool *aMixed, nsAString &aOutColor)
   nsresult res = GetSelectedOrParentTableElement(tagName,
                                                  &selectedCount,
                                                  getter_AddRefs(element));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   NS_NAMED_LITERAL_STRING(styleName, "bgcolor"); 
 
@@ -2449,7 +2449,7 @@ nsHTMLEditor::GetHTMLBackgroundColorState(PRBool *aMixed, nsAString &aOutColor)
   {
     // We are in a cell or selected table
     res = element->GetAttribute(styleName, aOutColor);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // Done if we have a color explicitly set
     if (!aOutColor.IsEmpty())
@@ -2462,7 +2462,7 @@ nsHTMLEditor::GetHTMLBackgroundColorState(PRBool *aMixed, nsAString &aOutColor)
     // from nested cells/tables, so search up parent chain
     nsCOMPtr<nsIDOMNode> parentNode;
     res = element->GetParentNode(getter_AddRefs(parentNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     element = do_QueryInterface(parentNode);
   }
 
@@ -2537,7 +2537,7 @@ nsHTMLEditor::MakeOrChangeList(const nsAString& aListType, PRBool entireList, co
   
   // pre-process
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   nsTextRulesInfo ruleInfo(nsTextEditRules::kMakeList);
@@ -2552,14 +2552,14 @@ nsHTMLEditor::MakeOrChangeList(const nsAString& aListType, PRBool entireList, co
     // Find out if the selection is collapsed:
     PRBool isCollapsed;
     res = selection->GetIsCollapsed(&isCollapsed);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     nsCOMPtr<nsIDOMNode> node;
     PRInt32 offset;
   
     res = GetStartNodeAndOffset(selection, getter_AddRefs(node), &offset);
     if (!node) res = NS_ERROR_FAILURE;
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   
     if (isCollapsed)
     {
@@ -2580,19 +2580,19 @@ nsHTMLEditor::MakeOrChangeList(const nsAString& aListType, PRBool entireList, co
       {
         // we need to split up to the child of parent
         res = SplitNodeDeep(topChild, node, offset, &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
 
       // make a list
       nsCOMPtr<nsIDOMNode> newList;
       res = CreateNode(aListType, parent, offset, getter_AddRefs(newList));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // make a list item
       nsCOMPtr<nsIDOMNode> newItem;
       res = CreateNode(NS_LITERAL_STRING("li"), newList, 0, getter_AddRefs(newItem));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = selection->Collapse(newItem,0);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   
@@ -2618,7 +2618,7 @@ nsHTMLEditor::RemoveList(const nsAString& aListType)
   
   // pre-process
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   nsTextRulesInfo ruleInfo(nsTextEditRules::kRemoveList);
@@ -2651,7 +2651,7 @@ nsHTMLEditor::MakeDefinitionItem(const nsAString& aItemType)
   
   // pre-process
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   nsTextRulesInfo ruleInfo(nsTextEditRules::kMakeDefListItem);
   ruleInfo.blockType = &aItemType;
@@ -2684,7 +2684,7 @@ nsHTMLEditor::InsertBasicBlock(const nsAString& aBlockType)
   
   // pre-process
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   nsTextRulesInfo ruleInfo(nsTextEditRules::kMakeBasicBlock);
   ruleInfo.blockType = &aBlockType;
@@ -2696,14 +2696,14 @@ nsHTMLEditor::InsertBasicBlock(const nsAString& aBlockType)
     // Find out if the selection is collapsed:
     PRBool isCollapsed;
     res = selection->GetIsCollapsed(&isCollapsed);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     nsCOMPtr<nsIDOMNode> node;
     PRInt32 offset;
   
     res = GetStartNodeAndOffset(selection, getter_AddRefs(node), &offset);
     if (!node) res = NS_ERROR_FAILURE;
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   
     if (isCollapsed)
     {
@@ -2724,17 +2724,17 @@ nsHTMLEditor::InsertBasicBlock(const nsAString& aBlockType)
       {
         // we need to split up to the child of parent
         res = SplitNodeDeep(topChild, node, offset, &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
 
       // make a block
       nsCOMPtr<nsIDOMNode> newBlock;
       res = CreateNode(aBlockType, parent, offset, getter_AddRefs(newBlock));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     
       // reposition selection to inside the block
       res = selection->Collapse(newBlock,0);
-      if (NS_FAILED(res)) return res;  
+      NS_ENSURE_SUCCESS(res, res);  
     }
   }
 
@@ -2765,7 +2765,7 @@ nsHTMLEditor::Indent(const nsAString& aIndent)
   // pre-process
   nsCOMPtr<nsISelection> selection;
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   nsTextRulesInfo ruleInfo(theAction);
@@ -2779,11 +2779,11 @@ nsHTMLEditor::Indent(const nsAString& aIndent)
     PRInt32 offset;
     PRBool isCollapsed;
     res = selection->GetIsCollapsed(&isCollapsed);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     res = GetStartNodeAndOffset(selection, getter_AddRefs(node), &offset);
     if (!node) res = NS_ERROR_FAILURE;
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   
     if (aIndent.EqualsLiteral("indent"))
     {
@@ -2806,23 +2806,23 @@ nsHTMLEditor::Indent(const nsAString& aIndent)
         {
           // we need to split up to the child of parent
           res = SplitNodeDeep(topChild, node, offset, &offset);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
 
         // make a blockquote
         nsCOMPtr<nsIDOMNode> newBQ;
         res = CreateNode(bq, parent, offset, getter_AddRefs(newBQ));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // put a space in it so layout will draw the list item
         res = selection->Collapse(newBQ,0);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = InsertText(NS_LITERAL_STRING(" "));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         // reposition selection to before the space character
         res = GetStartNodeAndOffset(selection, getter_AddRefs(node), &offset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = selection->Collapse(node,0);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
   }
@@ -2847,7 +2847,7 @@ nsHTMLEditor::Align(const nsAString& aAlignType)
   // Find out if the selection is collapsed:
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   nsTextRulesInfo ruleInfo(nsTextEditRules::kAlign);
   ruleInfo.alignType = &aAlignType;
@@ -2875,7 +2875,7 @@ nsHTMLEditor::GetElementOrParentByTagName(const nsAString& aTagName, nsIDOMNode
     // If no node supplied, get it from anchor node of current selection
     nsCOMPtr<nsISelection>selection;
     res = GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!selection) return NS_ERROR_NULL_POINTER;
 
     nsCOMPtr<nsIDOMNode> anchorNode;
@@ -2993,7 +2993,7 @@ nsHTMLEditor::GetSelectedElement(const nsAString& aTagName, nsIDOMElement** aRet
   // First look for a single element in selection
   nsCOMPtr<nsISelection>selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));
 
@@ -3013,26 +3013,26 @@ nsHTMLEditor::GetSelectedElement(const nsAString& aTagName, nsIDOMElement** aRet
   nsCOMPtr<nsIDOMElement> selectedElement;
   nsCOMPtr<nsIDOMRange> range;
   res = selection->GetRangeAt(0, getter_AddRefs(range));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMNode> startParent;
   PRInt32 startOffset, endOffset;
   res = range->GetStartContainer(getter_AddRefs(startParent));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = range->GetStartOffset(&startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMNode> endParent;
   res = range->GetEndContainer(getter_AddRefs(endParent));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = range->GetEndOffset(&endOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // Optimization for a single selected element
   if (startParent && startParent == endParent && (endOffset-startOffset) == 1)
   {
     nsCOMPtr<nsIDOMNode> selectedNode = GetChildAt(startParent, startOffset);
-    if (NS_FAILED(res)) return NS_OK;
+    NS_ENSURE_SUCCESS(res, NS_OK);
     if (selectedNode)
     {
       selectedNode->GetNodeName(domTagName);
@@ -3058,14 +3058,14 @@ nsHTMLEditor::GetSelectedElement(const nsAString& aTagName, nsIDOMElement** aRet
       //  included a collapsed selection (just a caret in a link)
       nsCOMPtr<nsIDOMNode> anchorNode;
       res = selection->GetAnchorNode(getter_AddRefs(anchorNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       PRInt32 anchorOffset = -1;
       if (anchorNode)
         selection->GetAnchorOffset(&anchorOffset);
     
       nsCOMPtr<nsIDOMNode> focusNode;
       res = selection->GetFocusNode(getter_AddRefs(focusNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       PRInt32 focusOffset = -1;
       if (focusNode)
         selection->GetFocusOffset(&focusOffset);
@@ -3142,7 +3142,7 @@ nsHTMLEditor::GetSelectedElement(const nsAString& aTagName, nsIDOMElement** aRet
           nsCOMPtr<nsIDOMRange> currange( do_QueryInterface(currentItem) );
           nsCOMPtr<nsIContentIterator> iter =
             do_CreateInstance("@mozilla.org/content/post-content-iterator;1", &res);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
 
           iter->Init(currange);
           // loop through the content iterator for each content node
@@ -3260,15 +3260,15 @@ nsHTMLEditor::CreateElementWithDefaults(const nsAString& aTagName, nsIDOMElement
     // Note that we read the user's attributes for these from prefs (in InsertHLine JS)
     res = SetAttributeOrEquivalent(newElement, NS_LITERAL_STRING("width"),
                                    NS_LITERAL_STRING("100%"), PR_TRUE);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = SetAttributeOrEquivalent(newElement, NS_LITERAL_STRING("size"),
                                    NS_LITERAL_STRING("2"), PR_TRUE);
   } else if (TagName.EqualsLiteral("table"))
   {
     res = newElement->SetAttribute(NS_LITERAL_STRING("cellpadding"),NS_LITERAL_STRING("2"));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = newElement->SetAttribute(NS_LITERAL_STRING("cellspacing"),NS_LITERAL_STRING("2"));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = newElement->SetAttribute(NS_LITERAL_STRING("border"),NS_LITERAL_STRING("1"));
   } else if (TagName.EqualsLiteral("td"))
   {
@@ -3302,7 +3302,7 @@ nsHTMLEditor::InsertLinkAroundSelection(nsIDOMElement* aAnchorElement)
   {
     res = NS_ERROR_NULL_POINTER;
   }
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   PRBool isCollapsed;
@@ -3321,7 +3321,7 @@ nsHTMLEditor::InsertLinkAroundSelection(nsIDOMElement* aAnchorElement)
     {
       nsAutoString href;
       res = anchor->GetHref(href);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!href.IsEmpty())      
       {
         nsAutoEditBatch beginBatching(this);
@@ -3340,7 +3340,7 @@ nsHTMLEditor::InsertLinkAroundSelection(nsIDOMElement* aAnchorElement)
         {
           nsCOMPtr<nsIDOMNode> attrNode;
           res = attrMap->Item(i, getter_AddRefs(attrNode));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
 
           if (attrNode)
           {
@@ -3353,13 +3353,13 @@ nsHTMLEditor::InsertLinkAroundSelection(nsIDOMElement* aAnchorElement)
               value.Truncate();
 
               res = attribute->GetName(name);
-              if (NS_FAILED(res)) return res;
+              NS_ENSURE_SUCCESS(res, res);
 
               res = attribute->GetValue(value);
-              if (NS_FAILED(res)) return res;
+              NS_ENSURE_SUCCESS(res, res);
 
               res = SetInlineProperty(nsEditProperty::a, name, value);
-              if (NS_FAILED(res)) return res;
+              NS_ENSURE_SUCCESS(res, res);
             }
           }
         }
@@ -3380,7 +3380,7 @@ nsHTMLEditor::SetHTMLBackgroundColor(const nsAString& aColor)
   nsAutoString tagName;
   nsresult res = GetSelectedOrParentTableElement(tagName, &selectedCount,
                                                  getter_AddRefs(element));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   PRBool setColor = !aColor.IsEmpty();
 
@@ -3447,7 +3447,7 @@ nsHTMLEditor::GetLinkedObjects(nsISupportsArray** aNodeList)
   nsresult res;
 
   res = NS_NewISupportsArray(aNodeList);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!*aNodeList) return NS_ERROR_NULL_POINTER;
 
   nsCOMPtr<nsIContentIterator> iter =
@@ -3769,7 +3769,7 @@ nsHTMLEditor::GetEmbeddedObjects(nsISupportsArray** aNodeList)
   nsresult res;
 
   res = NS_NewISupportsArray(aNodeList);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!*aNodeList) return NS_ERROR_NULL_POINTER;
 
   nsCOMPtr<nsIContentIterator> iter =
@@ -3968,7 +3968,7 @@ static nsresult SetSelectionAroundHeadChildren(nsCOMPtr<nsISelection> aSelection
 
   nsCOMPtr<nsIDOMNodeList>nodeList; 
   res = doc->GetElementsByTagName(NS_LITERAL_STRING("head"), getter_AddRefs(nodeList));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!nodeList) return NS_ERROR_NULL_POINTER;
 
   PRUint32 count; 
@@ -3977,17 +3977,17 @@ static nsresult SetSelectionAroundHeadChildren(nsCOMPtr<nsISelection> aSelection
 
   nsCOMPtr<nsIDOMNode> headNode;
   res = nodeList->Item(0, getter_AddRefs(headNode)); 
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!headNode) return NS_ERROR_NULL_POINTER;
 
   // Collapse selection to before first child of the head,
   res = aSelection->Collapse(headNode, 0);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   //  then extend it to just after
   nsCOMPtr<nsIDOMNodeList> childNodes;
   res = headNode->GetChildNodes(getter_AddRefs(childNodes));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!childNodes) return NS_ERROR_NULL_POINTER;
   PRUint32 childCount;
   childNodes->GetLength(&childCount);
@@ -4000,14 +4000,14 @@ nsHTMLEditor::GetHeadContentsAsHTML(nsAString& aOutputString)
 {
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   // Save current selection
   nsAutoSelectionReset selectionResetter(selection, this);
 
   res = SetSelectionAroundHeadChildren(selection, mDocWeak);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   res = OutputToString(NS_LITERAL_STRING("text/html"),
                        nsIDocumentEncoder::OutputSelectionOnly,
@@ -4201,7 +4201,7 @@ nsHTMLEditor::SelectEntireDocument(nsISelection *aSelection)
   // is doc empty?
   PRBool bDocIsEmpty;
   nsresult res = mRules->DocumentIsEmpty(&bDocIsEmpty);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
     
   if (bDocIsEmpty)
   {
@@ -4481,7 +4481,7 @@ nsHTMLEditor::CollapseAdjacentTextNodes(nsIDOMRange *aInRange)
   nsresult result;
   nsCOMPtr<nsIContentIterator> iter =
     do_CreateInstance("@mozilla.org/content/subtree-content-iterator;1", &result);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   iter->Init(aInRange);
 
@@ -4509,15 +4509,15 @@ nsHTMLEditor::CollapseAdjacentTextNodes(nsIDOMRange *aInRange)
     nsCOMPtr<nsIDOMNode> prevSibOfRightNode;
     result =
       rightTextNode->GetPreviousSibling(getter_AddRefs(prevSibOfRightNode));
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     if (prevSibOfRightNode && (prevSibOfRightNode == leftTextNode))
     {
       nsCOMPtr<nsIDOMNode> parent;
       result = rightTextNode->GetParentNode(getter_AddRefs(parent));
-      if (NS_FAILED(result)) return result;
+      NS_ENSURE_SUCCESS(result, result);
       if (!parent) return NS_ERROR_NULL_POINTER;
       result = JoinNodes(leftTextNode, rightTextNode, parent);
-      if (NS_FAILED(result)) return result;
+      NS_ENSURE_SUCCESS(result, result);
     }
 
     textNodes.RemoveElementAt(0); // remove the leftmost text node from the list
@@ -4562,7 +4562,7 @@ nsHTMLEditor::RemoveBlockContainer(nsIDOMNode *inNode)
   // trailing br.
   
   res = GetFirstEditableChild(inNode, address_of(child));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   if (child)  // the case of inNode not being empty
   {
@@ -4573,16 +4573,16 @@ nsHTMLEditor::RemoveBlockContainer(nsIDOMNode *inNode)
     // 4) either is null
     
     res = GetPriorHTMLSibling(inNode, address_of(sibling));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (sibling && !IsBlockNode(sibling) && !nsTextEditUtils::IsBreak(sibling))
     {
       res = GetFirstEditableChild(inNode, address_of(child));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (child && !IsBlockNode(child))
       {
         // insert br node
         res = CreateBR(inNode, 0, address_of(unused));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     
@@ -4593,19 +4593,19 @@ nsHTMLEditor::RemoveBlockContainer(nsIDOMNode *inNode)
     // 4) either is null
 
     res = GetNextHTMLSibling(inNode, address_of(sibling));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (sibling && !IsBlockNode(sibling))
     {
       res = GetLastEditableChild(inNode, address_of(child));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (child && !IsBlockNode(child) && !nsTextEditUtils::IsBreak(child))
       {
         // insert br node
         PRUint32 len;
         res = GetLengthOfDOMNode(inNode, len);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         res = CreateBR(inNode, (PRInt32)len, address_of(unused));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
   }
@@ -4618,16 +4618,16 @@ nsHTMLEditor::RemoveBlockContainer(nsIDOMNode *inNode)
     // 4) following sibling of inNode is a br OR
     // 5) either is null
     res = GetPriorHTMLSibling(inNode, address_of(sibling));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (sibling && !IsBlockNode(sibling) && !nsTextEditUtils::IsBreak(sibling))
     {
       res = GetNextHTMLSibling(inNode, address_of(sibling));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (sibling && !IsBlockNode(sibling) && !nsTextEditUtils::IsBreak(sibling))
       {
         // insert br node
         res = CreateBR(inNode, 0, address_of(unused));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
   }
@@ -4652,7 +4652,7 @@ nsHTMLEditor::GetPriorHTMLSibling(nsIDOMNode *inNode, nsCOMPtr<nsIDOMNode> *outN
   while (1)
   {
     res = node->GetPreviousSibling(getter_AddRefs(temp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!temp) return NS_OK;  // return null sibling
     // if it's editable, we're done
     if (IsEditable(temp)) break;
@@ -4704,7 +4704,7 @@ nsHTMLEditor::GetNextHTMLSibling(nsIDOMNode *inNode, nsCOMPtr<nsIDOMNode> *outNo
   while (1)
   {
     res = node->GetNextSibling(getter_AddRefs(temp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!temp) return NS_OK;  // return null sibling
     // if it's editable, we're done
     if (IsEditable(temp)) break;
@@ -4750,7 +4750,7 @@ nsHTMLEditor::GetPriorHTMLNode(nsIDOMNode *inNode, nsCOMPtr<nsIDOMNode> *outNode
 {
   if (!outNode) return NS_ERROR_NULL_POINTER;
   nsresult res = GetPriorNode(inNode, PR_TRUE, address_of(*outNode), bNoBlockCrossing);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // if it's not in the body, then zero it out
   if (*outNode && !nsTextEditUtils::InBody(*outNode, this))
@@ -4769,7 +4769,7 @@ nsHTMLEditor::GetPriorHTMLNode(nsIDOMNode *inParent, PRInt32 inOffset, nsCOMPtr<
 {
   if (!outNode) return NS_ERROR_NULL_POINTER;
   nsresult res = GetPriorNode(inParent, inOffset, PR_TRUE, address_of(*outNode), bNoBlockCrossing);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // if it's not in the body, then zero it out
   if (*outNode && !nsTextEditUtils::InBody(*outNode, this))
@@ -4789,7 +4789,7 @@ nsHTMLEditor::GetNextHTMLNode(nsIDOMNode *inNode, nsCOMPtr<nsIDOMNode> *outNode,
 {
   if (!outNode) return NS_ERROR_NULL_POINTER;
   nsresult res = GetNextNode(inNode, PR_TRUE, address_of(*outNode), bNoBlockCrossing);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // if it's not in the body, then zero it out
   if (*outNode && !nsTextEditUtils::InBody(*outNode, this))
@@ -4808,7 +4808,7 @@ nsHTMLEditor::GetNextHTMLNode(nsIDOMNode *inParent, PRInt32 inOffset, nsCOMPtr<n
 {
   if (!outNode) return NS_ERROR_NULL_POINTER;
   nsresult res = GetNextNode(inParent, inOffset, PR_TRUE, address_of(*outNode), bNoBlockCrossing);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // if it's not in the body, then zero it out
   if (*outNode && !nsTextEditUtils::InBody(*outNode, this))
@@ -4831,10 +4831,10 @@ nsHTMLEditor::IsFirstEditableChild( nsIDOMNode *aNode, PRBool *aOutIsFirst)
   // find first editable child and compare it to aNode
   nsCOMPtr<nsIDOMNode> parent, firstChild;
   nsresult res = aNode->GetParentNode(getter_AddRefs(parent));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!parent) return NS_ERROR_FAILURE;
   res = GetFirstEditableChild(parent, address_of(firstChild));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   *aOutIsFirst = (firstChild.get() == aNode);
   return res;
@@ -4853,10 +4853,10 @@ nsHTMLEditor::IsLastEditableChild( nsIDOMNode *aNode, PRBool *aOutIsLast)
   // find last editable child and compare it to aNode
   nsCOMPtr<nsIDOMNode> parent, lastChild;
   nsresult res = aNode->GetParentNode(getter_AddRefs(parent));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!parent) return NS_ERROR_FAILURE;
   res = GetLastEditableChild(parent, address_of(lastChild));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   *aOutIsLast = (lastChild.get() == aNode);
   return res;
@@ -4875,13 +4875,13 @@ nsHTMLEditor::GetFirstEditableChild( nsIDOMNode *aNode, nsCOMPtr<nsIDOMNode> *aO
   // find first editable child
   nsCOMPtr<nsIDOMNode> child;
   nsresult res = aNode->GetFirstChild(getter_AddRefs(child));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   while (child && !IsEditable(child))
   {
     nsCOMPtr<nsIDOMNode> tmp;
     res = child->GetNextSibling(getter_AddRefs(tmp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!tmp) return NS_ERROR_FAILURE;
     child = tmp;
   }
@@ -4903,13 +4903,13 @@ nsHTMLEditor::GetLastEditableChild( nsIDOMNode *aNode, nsCOMPtr<nsIDOMNode> *aOu
   // find last editable child
   nsCOMPtr<nsIDOMNode> child;
   nsresult res = aNode->GetLastChild(getter_AddRefs(child));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   while (child && !IsEditable(child))
   {
     nsCOMPtr<nsIDOMNode> tmp;
     res = child->GetPreviousSibling(getter_AddRefs(tmp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!tmp) return NS_ERROR_FAILURE;
     child = tmp;
   }
@@ -4935,7 +4935,7 @@ nsHTMLEditor::GetFirstEditableLeaf( nsIDOMNode *aNode, nsCOMPtr<nsIDOMNode> *aOu
   {
     nsCOMPtr<nsIDOMNode> tmp;
     res = GetNextHTMLNode(child, address_of(tmp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!tmp) return NS_ERROR_FAILURE;
     
     // only accept nodes that are descendants of aNode
@@ -4969,7 +4969,7 @@ nsHTMLEditor::GetLastEditableLeaf( nsIDOMNode *aNode, nsCOMPtr<nsIDOMNode> *aOut
   {
     nsCOMPtr<nsIDOMNode> tmp;
     res = GetPriorHTMLNode(child, address_of(tmp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!tmp) return NS_ERROR_FAILURE;
     
     // only accept nodes that are descendants of aNode
@@ -5024,7 +5024,7 @@ nsHTMLEditor::IsVisTextNode( nsIDOMNode *aNode,
   {
     nsCOMPtr<nsISelectionController> selCon;
     res = GetSelectionController(getter_AddRefs(selCon));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!selCon) return NS_ERROR_FAILURE;
     PRBool isVisible = PR_FALSE;
     // ask the selection controller for information about whether any
@@ -5034,7 +5034,7 @@ nsHTMLEditor::IsVisTextNode( nsIDOMNode *aNode,
     // in bed with frames anyway.  (this is a fix for bug 22227, and a
     // partial fix for bug 46209)
     res = selCon->CheckVisibility(aNode, 0, length, &isVisible);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (isVisible) 
     {
       *outIsEmptyNode = PR_FALSE;
@@ -5049,7 +5049,7 @@ nsHTMLEditor::IsVisTextNode( nsIDOMNode *aNode,
       PRInt32 outVisOffset=0;
       PRInt16 visType=0;
       res = wsRunObj.NextVisibleNode(aNode, 0, address_of(visNode), &outVisOffset, &visType);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if ( (visType == nsWSRunObject::eNormalWS) ||
            (visType == nsWSRunObject::eText) )
       {
@@ -5137,7 +5137,7 @@ nsHTMLEditor::IsEmptyNodeImpl( nsIDOMNode *aNode,
       if (nsEditor::IsTextNode(node))
       {
         res = IsVisTextNode(node, outIsEmptyNode, aSafeToAskFrames);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (!*outIsEmptyNode) return NS_OK;  // break out if we find we aren't emtpy
       }
       else  // an editable, non-text node.  we need to check it's content.
@@ -5172,7 +5172,7 @@ nsHTMLEditor::IsEmptyNodeImpl( nsIDOMNode *aNode,
           PRBool isEmptyNode = PR_TRUE;
           res = IsEmptyNodeImpl(node, &isEmptyNode, aSingleBRDoesntCount, 
                                 aListOrCellNotEmpty, aSafeToAskFrames, aSeenBR);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           if (!isEmptyNode) 
           { 
             // otherwise it ain't empty
@@ -5203,13 +5203,13 @@ nsHTMLEditor::SetAttributeOrEquivalent(nsIDOMElement * aElement,
     PRInt32 count;
     res = mHTMLCSSUtils->SetCSSEquivalentToHTMLStyle(aElement, nsnull, &aAttribute, &aValue, &count,
                                                      aSuppressTransaction);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (count) {
       // we found an equivalence ; let's remove the HTML attribute itself if it is set
       nsAutoString existingValue;
       PRBool wasSet = PR_FALSE;
       res = GetAttributeValue(aElement, aAttribute, existingValue, &wasSet);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (wasSet) {
         if (aSuppressTransaction)
           res = aElement->RemoveAttribute(aAttribute);
@@ -5227,7 +5227,7 @@ nsHTMLEditor::SetAttributeOrEquivalent(nsIDOMElement * aElement,
         nsAutoString existingValue;
         PRBool wasSet = PR_FALSE;
         res = GetAttributeValue(aElement, NS_LITERAL_STRING("style"), existingValue, &wasSet);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         existingValue.AppendLiteral(" ");
         existingValue.Append(aValue);
         if (aSuppressTransaction)
@@ -5266,13 +5266,13 @@ nsHTMLEditor::RemoveAttributeOrEquivalent(nsIDOMElement * aElement,
   if (useCSS && mHTMLCSSUtils) {
     res = mHTMLCSSUtils->RemoveCSSEquivalentToHTMLStyle(aElement, nsnull, &aAttribute, nsnull,
                                                         aSuppressTransaction);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   nsAutoString existingValue;
   PRBool wasSet = PR_FALSE;
   res = GetAttributeValue(aElement, aAttribute, existingValue, &wasSet);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (wasSet) {
     if (aSuppressTransaction)
       res = aElement->RemoveAttribute(aAttribute);
@@ -5320,7 +5320,7 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
   nsresult res;
   nsCOMPtr<nsISelection>selection;
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));
 
@@ -5335,13 +5335,13 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
   PRBool cancel, handled;
   nsTextRulesInfo ruleInfo(nsTextEditRules::kSetTextProperty);
   res = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!cancel && !handled)
   {
     // get selection range enumerator
     nsCOMPtr<nsIEnumerator> enumerator;
     res = selPriv->GetEnumerator(getter_AddRefs(enumerator));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!enumerator)    return NS_ERROR_FAILURE;
 
     // loop thru the ranges in the selection
@@ -5352,7 +5352,7 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
     while ((NS_ENUMERATOR_FALSE == enumerator->IsDone()))
     {
       res = enumerator->CurrentItem(getter_AddRefs(currentItem));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!currentItem)   return NS_ERROR_FAILURE;
       
       nsCOMPtr<nsIDOMRange> range( do_QueryInterface(currentItem) );
@@ -5361,13 +5361,13 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
       nsCOMPtr<nsIDOMNode> startNode, endNode;
       PRInt32 startOffset, endOffset;
       res = range->GetStartContainer(getter_AddRefs(startNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = range->GetEndContainer(getter_AddRefs(endNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = range->GetStartOffset(&startOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = range->GetEndOffset(&endOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if ((startNode == endNode) && IsTextNode(startNode))
       {
         // let's find the block container of the text node
@@ -5380,7 +5380,7 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
           nsCOMPtr<nsIDOMElement> element = do_QueryInterface(blockParent);
           PRInt32 count;
           res = mHTMLCSSUtils->SetCSSEquivalentToHTMLStyle(element, nsnull, &bgcolor, &aColor, &count, PR_FALSE);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
       }
       else if ((startNode == endNode) && nsTextEditUtils::IsBody(startNode) && isCollapsed)
@@ -5389,7 +5389,7 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
         nsCOMPtr<nsIDOMElement> element = do_QueryInterface(startNode);
         PRInt32 count;
         res = mHTMLCSSUtils->SetCSSEquivalentToHTMLStyle(element, nsnull, &bgcolor, &aColor, &count, PR_FALSE);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       else if ((startNode == endNode) && (((endOffset-startOffset) == 1) || (!startOffset && !endOffset)))
       {
@@ -5398,7 +5398,7 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
         nsCOMPtr<nsIDOMNode> selectedNode = GetChildAt(startNode, startOffset);
         PRBool isBlock =PR_FALSE;
         res = NodeIsBlockStatic(selectedNode, &isBlock);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         nsCOMPtr<nsIDOMNode> blockParent = selectedNode;
         if (!isBlock) {
           blockParent = GetBlockNodeParent(selectedNode);
@@ -5409,7 +5409,7 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
           nsCOMPtr<nsIDOMElement> element = do_QueryInterface(blockParent);
           PRInt32 count;
           res = mHTMLCSSUtils->SetCSSEquivalentToHTMLStyle(element, nsnull, &bgcolor, &aColor, &count, PR_FALSE);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
       }
       else
@@ -5427,7 +5427,7 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
 
         nsCOMPtr<nsIContentIterator> iter =
           do_CreateInstance("@mozilla.org/content/subtree-content-iterator;1", &res);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (!iter)          return NS_ERROR_FAILURE;
 
         nsCOMArray<nsIDOMNode> arrayOfNodes;
@@ -5468,7 +5468,7 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
             nsCOMPtr<nsIDOMElement> element = do_QueryInterface(blockParent);
             PRInt32 count;
             res = mHTMLCSSUtils->SetCSSEquivalentToHTMLStyle(element, nsnull, &bgcolor, &aColor, &count, PR_FALSE);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
         }
         
@@ -5481,7 +5481,7 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
           // do we have a block here ?
           PRBool isBlock =PR_FALSE;
           res = NodeIsBlockStatic(node, &isBlock);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           nsCOMPtr<nsIDOMNode> blockParent = node;
           if (!isBlock) {
             // no we don't, let's find the block ancestor
@@ -5494,7 +5494,7 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
             PRInt32 count;
             // and set the property on it
             res = mHTMLCSSUtils->SetCSSEquivalentToHTMLStyle(element, nsnull, &bgcolor, &aColor, &count, PR_FALSE);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
         }
         arrayOfNodes.Clear();
@@ -5512,7 +5512,7 @@ nsHTMLEditor::SetCSSBackgroundColor(const nsAString& aColor)
             nsCOMPtr<nsIDOMElement> element = do_QueryInterface(blockParent);
             PRInt32 count;
             res = mHTMLCSSUtils->SetCSSEquivalentToHTMLStyle(element, nsnull, &bgcolor, &aColor, &count, PR_FALSE);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
         }
       }
@@ -5588,7 +5588,7 @@ nsHTMLEditor::CopyLastEditableChildStyles(nsIDOMNode * aPreviousBlock, nsIDOMNod
   while (NS_SUCCEEDED(res) && child)
   {
     res = DeleteNode(child);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = aNewBlock->GetFirstChild(getter_AddRefs(child));
   }
   // now find and clone the styles
@@ -5597,12 +5597,12 @@ nsHTMLEditor::CopyLastEditableChildStyles(nsIDOMNode * aPreviousBlock, nsIDOMNod
   while (tmp) {
     child = tmp;
     res = GetLastEditableChild(child, address_of(tmp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   while (child && nsTextEditUtils::IsBreak(child)) {
     nsCOMPtr<nsIDOMNode> priorNode;
     res = GetPriorHTMLNode(child, address_of(priorNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     child = priorNode;
   }
   nsCOMPtr<nsIDOMNode> newStyles = nsnull, deepestStyle = nsnull;
@@ -5615,26 +5615,26 @@ nsHTMLEditor::CopyLastEditableChildStyles(nsIDOMNode * aPreviousBlock, nsIDOMNod
       if (newStyles) {
         nsCOMPtr<nsIDOMNode> newContainer;
         res = InsertContainerAbove(newStyles, address_of(newContainer), domTagName);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         newStyles = newContainer;
       }
       else {
         res = CreateNode(domTagName, aNewBlock, 0, getter_AddRefs(newStyles));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         deepestStyle = newStyles;
       }
       res = CloneAttributes(newStyles, child);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     nsCOMPtr<nsIDOMNode> tmp;
     res = child->GetParentNode(getter_AddRefs(tmp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     child = tmp;
   }
   if (deepestStyle) {
     nsCOMPtr<nsIDOMNode> outBRNode;
     res = CreateBR(deepestStyle, 0, address_of(outBRNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // Getters must addref
     *aOutBrNode = outBRNode;
     NS_ADDREF(*aOutBrNode);
@@ -5668,7 +5668,7 @@ nsresult
 nsHTMLEditor::EndUpdateViewBatch()
 {
   nsresult res = nsEditor::EndUpdateViewBatch();
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // We may need to show resizing handles or update existing ones after
   // all transactions are done. This way of doing is preferred to DOM
@@ -5679,7 +5679,7 @@ nsHTMLEditor::EndUpdateViewBatch()
   if (mUpdateCount == 0) {
     nsCOMPtr<nsISelection> selection;
     res = GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!selection) return NS_ERROR_NOT_INITIALIZED;
     res = CheckSelectionStateForAnonymousButtons(selection);
   }
@@ -5703,48 +5703,48 @@ nsHTMLEditor::GetSelectionContainer(nsIDOMElement ** aReturn)
 
   PRBool bCollapsed;
   res = selection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMNode> focusNode;
 
   if (bCollapsed) {
     res = selection->GetFocusNode(getter_AddRefs(focusNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   else {
 
     PRInt32 rangeCount;
     res = selection->GetRangeCount(&rangeCount);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     if (rangeCount == 1) {
 
       nsCOMPtr<nsIDOMRange> range;
       res = selection->GetRangeAt(0, getter_AddRefs(range));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!range) return NS_ERROR_NULL_POINTER;
 
       nsCOMPtr<nsIDOMNode> startContainer, endContainer;
       res = range->GetStartContainer(getter_AddRefs(startContainer));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = range->GetEndContainer(getter_AddRefs(endContainer));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       PRInt32 startOffset, endOffset;
       res = range->GetStartOffset(&startOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = range->GetEndOffset(&endOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       nsCOMPtr<nsIDOMElement> focusElement;
       if (startContainer == endContainer && startOffset + 1 == endOffset) {
         res = GetSelectedElement(EmptyString(), getter_AddRefs(focusElement));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (focusElement)
           focusNode = do_QueryInterface(focusElement);
       }
       if (!focusNode) {
         res = range->GetCommonAncestorContainer(getter_AddRefs(focusNode));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     else {
@@ -5753,7 +5753,7 @@ nsHTMLEditor::GetSelectionContainer(nsIDOMElement ** aReturn)
       for (i = 0; i < rangeCount; i++)
       {
         res = selection->GetRangeAt(i, getter_AddRefs(range));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         nsCOMPtr<nsIDOMNode> startContainer;
         res = range->GetStartContainer(getter_AddRefs(startContainer));
         if (NS_FAILED(res)) continue;
@@ -5761,7 +5761,7 @@ nsHTMLEditor::GetSelectionContainer(nsIDOMElement ** aReturn)
           focusNode = startContainer;
         else if (focusNode != startContainer) {
           res = startContainer->GetParentNode(getter_AddRefs(focusNode));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           break;
         }
       }
@@ -5774,7 +5774,7 @@ nsHTMLEditor::GetSelectionContainer(nsIDOMElement ** aReturn)
     if (nsIDOMNode::TEXT_NODE == nodeType) {
       nsCOMPtr<nsIDOMNode> parent;
       res = focusNode->GetParentNode(getter_AddRefs(parent));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       focusNode = parent;
     }
   }
diff --git a/editor/libeditor/html/nsHTMLEditorEventListener.cpp b/editor/libeditor/html/nsHTMLEditorEventListener.cpp
index 40fcce7e9a6..7c1b56f95b4 100644
--- a/editor/libeditor/html/nsHTMLEditorEventListener.cpp
+++ b/editor/libeditor/html/nsHTMLEditorEventListener.cpp
@@ -102,7 +102,7 @@ nsHTMLEditorEventListener::MouseUp(nsIDOMEvent* aMouseEvent)
 
   nsCOMPtr<nsIDOMEventTarget> target;
   nsresult res = aMouseEvent->GetTarget(getter_AddRefs(target));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!target) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsIDOMElement> element = do_QueryInterface(target);
 
@@ -132,14 +132,14 @@ nsHTMLEditorEventListener::MouseDown(nsIDOMEvent* aMouseEvent)
   // But eDOMEvents_contextmenu and NS_CONTEXTMENU is not exposed in any event interface :-(
   PRUint16 buttonNumber;
   nsresult res = mouseEvent->GetButton(&buttonNumber);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   PRBool isContextClick;
 
 #if defined(XP_MAC) || defined(XP_MACOSX)
   // Ctrl+Click for context menu
   res = mouseEvent->GetCtrlKey(&isContextClick);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 #else
   // Right mouse button for Windows, UNIX
   isContextClick = buttonNumber == 2;
@@ -147,12 +147,12 @@ nsHTMLEditorEventListener::MouseDown(nsIDOMEvent* aMouseEvent)
   
   PRInt32 clickCount;
   res = mouseEvent->GetDetail(&clickCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMEventTarget> target;
   nsCOMPtr<nsIDOMNSEvent> internalEvent = do_QueryInterface(aMouseEvent);
   res = internalEvent->GetExplicitOriginalTarget(getter_AddRefs(target));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!target) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsIDOMElement> element = do_QueryInterface(target);
 
@@ -170,11 +170,11 @@ nsHTMLEditorEventListener::MouseDown(nsIDOMEvent* aMouseEvent)
     PRInt32 offset = 0;
 
     res = uiEvent->GetRangeParent(getter_AddRefs(parent));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!parent) return NS_ERROR_FAILURE;
 
     res = uiEvent->GetRangeOffset(&offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // Detect if mouse point is within current selection for context click
     PRBool nodeIsInSelection = PR_FALSE;
@@ -186,7 +186,7 @@ nsHTMLEditorEventListener::MouseDown(nsIDOMEvent* aMouseEvent)
       {
         PRInt32 rangeCount;
         res = selection->GetRangeCount(&rangeCount);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
 
         for (PRInt32 i = 0; i < rangeCount; i++)
         {
@@ -223,7 +223,7 @@ nsHTMLEditorEventListener::MouseDown(nsIDOMEvent* aMouseEvent)
           // Get enclosing link if in text so we can select the link
           nsCOMPtr<nsIDOMElement> linkElement;
           res = htmlEditor->GetElementOrParentByTagName(NS_LITERAL_STRING("href"), node, getter_AddRefs(linkElement));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           if (linkElement)
             element = linkElement;
         }
@@ -300,7 +300,7 @@ nsHTMLEditorEventListener::MouseClick(nsIDOMEvent* aMouseEvent)
 
   nsCOMPtr<nsIDOMEventTarget> target;
   nsresult res = aMouseEvent->GetTarget(getter_AddRefs(target));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!target) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsIDOMElement> element = do_QueryInterface(target);
 
diff --git a/editor/libeditor/html/nsHTMLEditorLog.cpp b/editor/libeditor/html/nsHTMLEditorLog.cpp
index f922529718a..6b4643ef834 100644
--- a/editor/libeditor/html/nsHTMLEditorLog.cpp
+++ b/editor/libeditor/html/nsHTMLEditorLog.cpp
@@ -845,7 +845,7 @@ nsHTMLEditorLog::StartLogging(nsIFile *aLogFile)
   }
 
   result = NS_NewLocalFileOutputStream(getter_AddRefs(mFileStream), aLogFile);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   if (mTxnMgr)
   {
diff --git a/editor/libeditor/html/nsHTMLEditorStyle.cpp b/editor/libeditor/html/nsHTMLEditorStyle.cpp
index 62ae6d5bc4f..b946b011a49 100644
--- a/editor/libeditor/html/nsHTMLEditorStyle.cpp
+++ b/editor/libeditor/html/nsHTMLEditorStyle.cpp
@@ -132,7 +132,7 @@ NS_IMETHODIMP nsHTMLEditor::SetInlineProperty(nsIAtom *aProperty,
 
   nsCOMPtr<nsISelection>selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));
 
@@ -154,13 +154,13 @@ NS_IMETHODIMP nsHTMLEditor::SetInlineProperty(nsIAtom *aProperty,
   PRBool cancel, handled;
   nsTextRulesInfo ruleInfo(nsTextEditRules::kSetTextProperty);
   res = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!cancel && !handled)
   {
     // get selection range enumerator
     nsCOMPtr<nsIEnumerator> enumerator;
     res = selPriv->GetEnumerator(getter_AddRefs(enumerator));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!enumerator)    return NS_ERROR_FAILURE;
 
     // loop thru the ranges in the selection
@@ -169,21 +169,21 @@ NS_IMETHODIMP nsHTMLEditor::SetInlineProperty(nsIAtom *aProperty,
     while ((NS_ENUMERATOR_FALSE == enumerator->IsDone()))
     {
       res = enumerator->CurrentItem(getter_AddRefs(currentItem));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!currentItem)   return NS_ERROR_FAILURE;
       
       nsCOMPtr<nsIDOMRange> range( do_QueryInterface(currentItem) );
 
       // adjust range to include any ancestors who's children are entirely selected
       res = PromoteInlineRange(range);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       
       // check for easy case: both range endpoints in same text node
       nsCOMPtr<nsIDOMNode> startNode, endNode;
       res = range->GetStartContainer(getter_AddRefs(startNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = range->GetEndContainer(getter_AddRefs(endNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if ((startNode == endNode) && IsTextNode(startNode))
       {
         PRInt32 startOffset, endOffset;
@@ -191,7 +191,7 @@ NS_IMETHODIMP nsHTMLEditor::SetInlineProperty(nsIAtom *aProperty,
         range->GetEndOffset(&endOffset);
         nsCOMPtr<nsIDOMCharacterData> nodeAsText = do_QueryInterface(startNode);
         res = SetInlinePropertyOnTextNode(nodeAsText, startOffset, endOffset, aProperty, &aAttribute, &aValue);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       else
       {
@@ -208,7 +208,7 @@ NS_IMETHODIMP nsHTMLEditor::SetInlineProperty(nsIAtom *aProperty,
 
         nsCOMPtr<nsIContentIterator> iter =
           do_CreateInstance("@mozilla.org/content/subtree-content-iterator;1", &res);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (!iter)          return NS_ERROR_FAILURE;
 
         nsCOMArray<nsIDOMNode> arrayOfNodes;
@@ -247,7 +247,7 @@ NS_IMETHODIMP nsHTMLEditor::SetInlineProperty(nsIAtom *aProperty,
           range->GetStartOffset(&startOffset);
           nodeAsText->GetLength(&textLen);
           res = SetInlinePropertyOnTextNode(nodeAsText, startOffset, textLen, aProperty, &aAttribute, &aValue);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         
         // then loop through the list, set the property on each node
@@ -257,7 +257,7 @@ NS_IMETHODIMP nsHTMLEditor::SetInlineProperty(nsIAtom *aProperty,
         {
           node = arrayOfNodes[j];
           res = SetInlinePropertyOnNode(node, aProperty, &aAttribute, &aValue);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         arrayOfNodes.Clear();
         
@@ -270,7 +270,7 @@ NS_IMETHODIMP nsHTMLEditor::SetInlineProperty(nsIAtom *aProperty,
           PRInt32 endOffset;
           range->GetEndOffset(&endOffset);
           res = SetInlinePropertyOnTextNode(nodeAsText, 0, endOffset, aProperty, &aAttribute, &aValue);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
       }
       enumerator->Next();
@@ -297,7 +297,7 @@ nsHTMLEditor::SetInlinePropertyOnTextNode( nsIDOMCharacterData *aTextNode,
   if (!aTextNode) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsIDOMNode> parent;
   nsresult res = aTextNode->GetParentNode(getter_AddRefs(parent));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsAutoString tagString;
   aProperty->ToString(tagString);
@@ -340,14 +340,14 @@ nsHTMLEditor::SetInlinePropertyOnTextNode( nsIDOMCharacterData *aTextNode,
   {
     // we need to split off back of text node
     res = SplitNode(node, aEndOffset, getter_AddRefs(tmp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     node = tmp;  // remember left node
   }
   if ( aStartOffset )
   {
     // we need to split off front of text node
     res = SplitNode(node, aStartOffset, getter_AddRefs(tmp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   
   // look for siblings that are correct type of node
@@ -417,11 +417,11 @@ nsHTMLEditor::SetInlinePropertyOnNode( nsIDOMNode *aNode,
       // first we have to remove occurences of the same style hint in the
       // children of the aNode
       res = RemoveStyleInside(tmp, aProperty, aAttribute, PR_TRUE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       PRInt32 count;
       // then we add the css styles corresponding to the HTML style request
       res = mHTMLCSSUtils->SetCSSEquivalentToHTMLStyle(element, aProperty, aAttribute, aValue, &count, PR_FALSE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       nsCOMPtr<nsIDOMNode> nextSibling, previousSibling;
       GetNextHTMLSibling(tmp, address_of(nextSibling));
@@ -430,13 +430,13 @@ nsHTMLEditor::SetInlinePropertyOnNode( nsIDOMNode *aNode,
       {
         nsCOMPtr<nsIDOMNode> mergeParent;
         res = tmp->GetParentNode(getter_AddRefs(mergeParent));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (previousSibling &&
             nsEditor::NodeIsType(previousSibling, nsEditProperty::span) &&
             NodesSameType(tmp, previousSibling))
         {
           res = JoinNodes(previousSibling, tmp, mergeParent);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         if (nextSibling &&
             nsEditor::NodeIsType(nextSibling, nsEditProperty::span) &&
@@ -461,7 +461,7 @@ nsHTMLEditor::SetInlinePropertyOnNode( nsIDOMNode *aNode,
     // just set the attribute on it.
     // but first remove any contrary style in it's children.
     res = RemoveStyleInside(aNode, aProperty, aAttribute, PR_TRUE);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     nsCOMPtr<nsIDOMElement> elem = do_QueryInterface(aNode);
     return SetAttribute(elem, *aAttribute, *aValue);
   }
@@ -492,13 +492,13 @@ nsHTMLEditor::SetInlinePropertyOnNode( nsIDOMNode *aNode,
       // ok, chuck it in it's very own container
       res = InsertContainerAbove(aNode, address_of(tmp), tag, aAttribute, aValue);
     }
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     return RemoveStyleInside(aNode, aProperty, aAttribute);
   }
   // none of the above?  then cycle through the children.
   nsCOMPtr<nsIDOMNodeList> childNodes;
   res = aNode->GetChildNodes(getter_AddRefs(childNodes));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (childNodes)
   {
     PRInt32 j;
@@ -526,7 +526,7 @@ nsHTMLEditor::SetInlinePropertyOnNode( nsIDOMNode *aNode,
       {
         node = arrayOfNodes[j];
         res = SetInlinePropertyOnNode(node, aProperty, aAttribute, aValue);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       arrayOfNodes.Clear();
     }
@@ -545,13 +545,13 @@ nsresult nsHTMLEditor::SplitStyleAboveRange(nsIDOMRange *inRange,
   PRInt32 startOffset, endOffset, origStartOffset;
   
   res = inRange->GetStartContainer(getter_AddRefs(startNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetStartOffset(&startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetEndContainer(getter_AddRefs(endNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetEndOffset(&endOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   origStartNode = startNode;
   origStartOffset = startOffset;
@@ -560,16 +560,16 @@ nsresult nsHTMLEditor::SplitStyleAboveRange(nsIDOMRange *inRange,
   {
     nsAutoTrackDOMPoint tracker(mRangeUpdater, address_of(endNode), &endOffset);
     res = SplitStyleAbovePoint(address_of(startNode), &startOffset, aProperty, aAttribute);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   // second verse, same as the first...
   res = SplitStyleAbovePoint(address_of(endNode), &endOffset, aProperty, aAttribute);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // reset the range
   res = inRange->SetStart(startNode, startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->SetEnd(endNode, endOffset);
   return res;
 }
@@ -643,7 +643,7 @@ nsresult nsHTMLEditor::ApplyDefaultProperties()
     if (!propItem) 
       return NS_ERROR_NULL_POINTER;
     res = SetInlineProperty(propItem->tag, propItem->attr, propItem->value);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return res;
 }
@@ -665,7 +665,7 @@ nsresult nsHTMLEditor::RemoveStyleInside(nsIDOMNode *aNode,
     // cache next sibling since we might remove child
     child->GetNextSibling(getter_AddRefs(tmp));
     res = RemoveStyleInside(child, aProperty, aAttribute);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     child = tmp;
   }
 
@@ -859,13 +859,13 @@ nsresult nsHTMLEditor::PromoteRangeIfStartsOrEndsInNamedAnchor(nsIDOMRange *inRa
   PRInt32 startOffset, endOffset, tmpOffset;
   
   res = inRange->GetStartContainer(getter_AddRefs(startNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetStartOffset(&startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetEndContainer(getter_AddRefs(endNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetEndOffset(&endOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   tmp = startNode;
   while ( tmp && 
@@ -873,14 +873,14 @@ nsresult nsHTMLEditor::PromoteRangeIfStartsOrEndsInNamedAnchor(nsIDOMRange *inRa
           !nsHTMLEditUtils::IsNamedAnchor(tmp))
   {
     res = GetNodeLocation(tmp, address_of(parent), &tmpOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     tmp = parent;
   }
   if (!tmp) return NS_ERROR_NULL_POINTER;
   if (nsHTMLEditUtils::IsNamedAnchor(tmp))
   {
     res = GetNodeLocation(tmp, address_of(parent), &tmpOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     startNode = parent;
     startOffset = tmpOffset;
   }
@@ -891,20 +891,20 @@ nsresult nsHTMLEditor::PromoteRangeIfStartsOrEndsInNamedAnchor(nsIDOMRange *inRa
           !nsHTMLEditUtils::IsNamedAnchor(tmp))
   {
     res = GetNodeLocation(tmp, address_of(parent), &tmpOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     tmp = parent;
   }
   if (!tmp) return NS_ERROR_NULL_POINTER;
   if (nsHTMLEditUtils::IsNamedAnchor(tmp))
   {
     res = GetNodeLocation(tmp, address_of(parent), &tmpOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     endNode = parent;
     endOffset = tmpOffset + 1;
   }
 
   res = inRange->SetStart(startNode, startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->SetEnd(endNode, endOffset);
   return res;
 }
@@ -917,13 +917,13 @@ nsresult nsHTMLEditor::PromoteInlineRange(nsIDOMRange *inRange)
   PRInt32 startOffset, endOffset;
   
   res = inRange->GetStartContainer(getter_AddRefs(startNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetStartOffset(&startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetEndContainer(getter_AddRefs(endNode));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->GetEndOffset(&endOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   while ( startNode && 
           !nsTextEditUtils::IsBody(startNode) && 
@@ -931,7 +931,7 @@ nsresult nsHTMLEditor::PromoteInlineRange(nsIDOMRange *inRange)
           IsAtFrontOfNode(startNode, startOffset) )
   {
     res = GetNodeLocation(startNode, address_of(parent), &startOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     startNode = parent;
   }
   if (!startNode) return NS_ERROR_NULL_POINTER;
@@ -942,14 +942,14 @@ nsresult nsHTMLEditor::PromoteInlineRange(nsIDOMRange *inRange)
           IsAtEndOfNode(endNode, endOffset) )
   {
     res = GetNodeLocation(endNode, address_of(parent), &endOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     endNode = parent;
     endOffset++;  // we are AFTER this node
   }
   if (!endNode) return NS_ERROR_NULL_POINTER;
   
   res = inRange->SetStart(startNode, startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = inRange->SetEnd(endNode, endOffset);
   return res;
 }
@@ -1023,7 +1023,7 @@ nsHTMLEditor::GetInlinePropertyBase(nsIAtom *aProperty,
 
   nsCOMPtr<nsISelection>selection;
   result = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!selection) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));
 
@@ -1032,7 +1032,7 @@ nsHTMLEditor::GetInlinePropertyBase(nsIAtom *aProperty,
   nsCOMPtr<nsIDOMNode> collapsedNode;
   nsCOMPtr<nsIEnumerator> enumerator;
   result = selPriv->GetEnumerator(getter_AddRefs(enumerator));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!enumerator) return NS_ERROR_NULL_POINTER;
 
   enumerator->First(); 
@@ -1101,9 +1101,9 @@ nsHTMLEditor::GetInlinePropertyBase(nsIAtom *aProperty,
     nsCOMPtr<nsIDOMNode> endNode;
     PRInt32 endOffset;
     result = range->GetEndContainer(getter_AddRefs(endNode));
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     result = range->GetEndOffset(&endOffset);
-    if (NS_FAILED(result)) return result;
+    NS_ENSURE_SUCCESS(result, result);
     while (!iter->IsDone())
     {
       nsCOMPtr<nsIContent> content = do_QueryInterface(iter->GetCurrentNode());
@@ -1255,7 +1255,7 @@ NS_IMETHODIMP nsHTMLEditor::RemoveAllInlineProperties()
   nsAutoRules beginRulesSniffing(this, kOpResetTextProperties, nsIEditor::eNext);
 
   nsresult res = RemoveInlinePropertyImpl(nsnull, nsnull);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   return ApplyDefaultProperties();
 }
 
@@ -1272,7 +1272,7 @@ nsresult nsHTMLEditor::RemoveInlinePropertyImpl(nsIAtom *aProperty, const nsAStr
   nsresult res;
   nsCOMPtr<nsISelection>selection;
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
   nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));
 
@@ -1302,13 +1302,13 @@ nsresult nsHTMLEditor::RemoveInlinePropertyImpl(nsIAtom *aProperty, const nsAStr
   PRBool cancel, handled;
   nsTextRulesInfo ruleInfo(nsTextEditRules::kRemoveTextProperty);
   res = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!cancel && !handled)
   {
     // get selection range enumerator
     nsCOMPtr<nsIEnumerator> enumerator;
     res = selPriv->GetEnumerator(getter_AddRefs(enumerator));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!enumerator)    return NS_ERROR_FAILURE;
 
     // loop thru the ranges in the selection
@@ -1317,7 +1317,7 @@ nsresult nsHTMLEditor::RemoveInlinePropertyImpl(nsIAtom *aProperty, const nsAStr
     while ((NS_ENUMERATOR_FALSE == enumerator->IsDone()))
     {
       res = enumerator->CurrentItem(getter_AddRefs(currentItem));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!currentItem)   return NS_ERROR_FAILURE;
       
       nsCOMPtr<nsIDOMRange> range( do_QueryInterface(currentItem) );
@@ -1332,19 +1332,19 @@ nsresult nsHTMLEditor::RemoveInlinePropertyImpl(nsIAtom *aProperty, const nsAStr
         // adjust range to include any ancestors who's children are entirely selected
         res = PromoteInlineRange(range);
       }
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       // remove this style from ancestors of our range endpoints, 
       // splitting them as appropriate
       res = SplitStyleAboveRange(range, aProperty, aAttribute);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       // check for easy case: both range endpoints in same text node
       nsCOMPtr<nsIDOMNode> startNode, endNode;
       res = range->GetStartContainer(getter_AddRefs(startNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = range->GetEndContainer(getter_AddRefs(endNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if ((startNode == endNode) && IsTextNode(startNode))
       {
         // we're done with this range!
@@ -1380,7 +1380,7 @@ nsresult nsHTMLEditor::RemoveInlinePropertyImpl(nsIAtom *aProperty, const nsAStr
         // not the easy case.  range not contained in single text node. 
         nsCOMPtr<nsIContentIterator> iter =
           do_CreateInstance("@mozilla.org/content/subtree-content-iterator;1", &res);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (!iter)          return NS_ERROR_FAILURE;
 
         nsCOMArray<nsIDOMNode> arrayOfNodes;
@@ -1409,7 +1409,7 @@ nsresult nsHTMLEditor::RemoveInlinePropertyImpl(nsIAtom *aProperty, const nsAStr
         {
           node = arrayOfNodes[j];
           res = RemoveStyleInside(node, aProperty, aAttribute);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           if (useCSS && mHTMLCSSUtils->IsCSSEditableProperty(node, aProperty, aAttribute)) {
             // the HTML style defined by aProperty/aAttribute has a CSS equivalence
             // in this implementation for node
@@ -1468,13 +1468,13 @@ nsHTMLEditor::RelativeFontChange( PRInt32 aSizeChange)
   // Get the selection 
   nsCOMPtr<nsISelection>selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_FAILURE;
   nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));  
   // Is the selection collapsed?
   PRBool bCollapsed;
   res = selection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // if it's collapsed set typing state
   if (bCollapsed)
@@ -1490,7 +1490,7 @@ nsHTMLEditor::RelativeFontChange( PRInt32 aSizeChange)
     if (IsTextNode(selectedNode)) {
       nsCOMPtr<nsIDOMNode> parent;
       res = selectedNode->GetParentNode(getter_AddRefs(parent));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       selectedNode = parent;
     }
     nsAutoString tag;
@@ -1510,7 +1510,7 @@ nsHTMLEditor::RelativeFontChange( PRInt32 aSizeChange)
   // get selection range enumerator
   nsCOMPtr<nsIEnumerator> enumerator;
   res = selPriv->GetEnumerator(getter_AddRefs(enumerator));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!enumerator)    return NS_ERROR_FAILURE;
 
   // loop thru the ranges in the selection
@@ -1519,21 +1519,21 @@ nsHTMLEditor::RelativeFontChange( PRInt32 aSizeChange)
   while ((NS_ENUMERATOR_FALSE == enumerator->IsDone()))
   {
     res = enumerator->CurrentItem(getter_AddRefs(currentItem));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!currentItem)   return NS_ERROR_FAILURE;
     
     nsCOMPtr<nsIDOMRange> range( do_QueryInterface(currentItem) );
 
     // adjust range to include any ancestors who's children are entirely selected
     res = PromoteInlineRange(range);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     // check for easy case: both range endpoints in same text node
     nsCOMPtr<nsIDOMNode> startNode, endNode;
     res = range->GetStartContainer(getter_AddRefs(startNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = range->GetEndContainer(getter_AddRefs(endNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if ((startNode == endNode) && IsTextNode(startNode))
     {
       PRInt32 startOffset, endOffset;
@@ -1541,7 +1541,7 @@ nsHTMLEditor::RelativeFontChange( PRInt32 aSizeChange)
       range->GetEndOffset(&endOffset);
       nsCOMPtr<nsIDOMCharacterData> nodeAsText = do_QueryInterface(startNode);
       res = RelativeFontChangeOnTextNode(aSizeChange, nodeAsText, startOffset, endOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     else
     {
@@ -1558,7 +1558,7 @@ nsHTMLEditor::RelativeFontChange( PRInt32 aSizeChange)
 
       nsCOMPtr<nsIContentIterator> iter =
         do_CreateInstance("@mozilla.org/content/subtree-content-iterator;1", &res);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!iter)          return NS_ERROR_FAILURE;
 
       nsCOMArray<nsIDOMNode> arrayOfNodes;
@@ -1589,7 +1589,7 @@ nsHTMLEditor::RelativeFontChange( PRInt32 aSizeChange)
         {
           node = arrayOfNodes[j];
           res = RelativeFontChangeOnNode(aSizeChange, node);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         arrayOfNodes.Clear();
       }
@@ -1604,7 +1604,7 @@ nsHTMLEditor::RelativeFontChange( PRInt32 aSizeChange)
         range->GetStartOffset(&startOffset);
         nodeAsText->GetLength(&textLen);
         res = RelativeFontChangeOnTextNode(aSizeChange, nodeAsText, startOffset, textLen);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       if (IsTextNode(endNode) && IsEditable(endNode))
       {
@@ -1612,7 +1612,7 @@ nsHTMLEditor::RelativeFontChange( PRInt32 aSizeChange)
         PRInt32 endOffset;
         range->GetEndOffset(&endOffset);
         res = RelativeFontChangeOnTextNode(aSizeChange, nodeAsText, 0, endOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     enumerator->Next();
@@ -1638,7 +1638,7 @@ nsHTMLEditor::RelativeFontChangeOnTextNode( PRInt32 aSizeChange,
   nsresult res = NS_OK;
   nsCOMPtr<nsIDOMNode> parent;
   res = aTextNode->GetParentNode(getter_AddRefs(parent));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!CanContainTag(parent, NS_LITERAL_STRING("big"))) return NS_OK;
 
   nsCOMPtr<nsIDOMNode> tmp, node = do_QueryInterface(aTextNode);
@@ -1654,14 +1654,14 @@ nsHTMLEditor::RelativeFontChangeOnTextNode( PRInt32 aSizeChange,
   {
     // we need to split off back of text node
     res = SplitNode(node, aEndOffset, getter_AddRefs(tmp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     node = tmp;  // remember left node
   }
   if ( aStartOffset )
   {
     // we need to split off front of text node
     res = SplitNode(node, aStartOffset, getter_AddRefs(tmp));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   NS_NAMED_LITERAL_STRING(bigSize, "big");
@@ -1721,7 +1721,7 @@ nsHTMLEditor::RelativeFontChangeHelper( PRInt32 aSizeChange,
   {
     // cycle through children and adjust relative font size
     res = aNode->GetChildNodes(getter_AddRefs(childNodes));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (childNodes)
     {
       childNodes->GetLength(&childCount);
@@ -1731,7 +1731,7 @@ nsHTMLEditor::RelativeFontChangeHelper( PRInt32 aSizeChange,
         if ((NS_SUCCEEDED(res)) && (childNode))
         {
           res = RelativeFontChangeOnNode(aSizeChange, childNode);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
       }
     }
@@ -1740,7 +1740,7 @@ nsHTMLEditor::RelativeFontChangeHelper( PRInt32 aSizeChange,
   childNodes = nsnull;
   // now cycle through the children.
   res = aNode->GetChildNodes(getter_AddRefs(childNodes));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (childNodes)
   {
     childNodes->GetLength(&childCount);
@@ -1750,7 +1750,7 @@ nsHTMLEditor::RelativeFontChangeHelper( PRInt32 aSizeChange,
       if ((NS_SUCCEEDED(res)) && (childNode))
       {
         res = RelativeFontChangeHelper(aSizeChange, childNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
   }
@@ -1780,7 +1780,7 @@ nsHTMLEditor::RelativeFontChangeOnNode( PRInt32 aSizeChange,
   {
     // first populate any nested font tags that have the size attr set
     res = RelativeFontChangeHelper(aSizeChange, aNode);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // in that case, just remove this node and pull up the children
     res = RemoveContainer(aNode);
     return res;
@@ -1790,7 +1790,7 @@ nsHTMLEditor::RelativeFontChangeOnNode( PRInt32 aSizeChange,
   {
     // first populate any nested font tags that have the size attr set
     res = RelativeFontChangeHelper(aSizeChange, aNode);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // ok, chuck it in.
     // first look at siblings of aNode for matching bigs or smalls.
     // if we find one, move aNode into it.
@@ -1820,7 +1820,7 @@ nsHTMLEditor::RelativeFontChangeOnNode( PRInt32 aSizeChange,
   // each getting their own.  
   nsCOMPtr<nsIDOMNodeList> childNodes;
   res = aNode->GetChildNodes(getter_AddRefs(childNodes));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (childNodes)
   {
     PRInt32 j;
@@ -1833,7 +1833,7 @@ nsHTMLEditor::RelativeFontChangeOnNode( PRInt32 aSizeChange,
       if ((NS_SUCCEEDED(res)) && (childNode))
       {
         res = RelativeFontChangeOnNode(aSizeChange, childNode);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
   }
@@ -1853,7 +1853,7 @@ nsHTMLEditor::GetFontFaceState(PRBool *aMixed, nsAString &outFace)
   
   NS_NAMED_LITERAL_STRING(attr, "face");
   res = GetInlinePropertyBase(nsEditProperty::font, &attr, nsnull, &first, &any, &all, &outFace);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (any && !all) return res; // mixed
   if (all)
   {
@@ -1863,7 +1863,7 @@ nsHTMLEditor::GetFontFaceState(PRBool *aMixed, nsAString &outFace)
   
   // if there is no font face, check for tt
   res = GetInlinePropertyBase(nsEditProperty::tt, nsnull, nsnull, &first, &any, &all,nsnull);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (any && !all) return res; // mixed
   if (all)
   {
@@ -1893,7 +1893,7 @@ nsHTMLEditor::GetFontColorState(PRBool *aMixed, nsAString &aOutColor)
   PRBool first, any, all;
   
   res = GetInlinePropertyBase(nsEditProperty::font, &colorStr, nsnull, &first, &any, &all, &aOutColor);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (any && !all) return res; // mixed
   if (all)
   {
@@ -1939,10 +1939,10 @@ nsHTMLEditor::HasStyleOrIdOrClass(nsIDOMElement * aElement, PRBool *aHasStyleOrI
   PRBool isStyleSet;
   *aHasStyleOrIdOrClass = PR_TRUE;
   nsresult res = GetAttributeValue(aElement,  NS_LITERAL_STRING("style"), styleVal, &isStyleSet);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!isStyleSet || styleVal.IsEmpty()) {
     res = mHTMLCSSUtils->HasClassOrID(aElement, *aHasStyleOrIdOrClass);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return res;
 }
diff --git a/editor/libeditor/html/nsHTMLInlineTableEditor.cpp b/editor/libeditor/html/nsHTMLInlineTableEditor.cpp
index 1f1bc374b44..b57e4945f0d 100644
--- a/editor/libeditor/html/nsHTMLInlineTableEditor.cpp
+++ b/editor/libeditor/html/nsHTMLInlineTableEditor.cpp
@@ -162,7 +162,7 @@ nsHTMLEditor::DoInlineTableEditingAction(nsIDOMElement * aElement)
       anonElement) {
     nsAutoString anonclass;
     nsresult res = aElement->GetAttribute(NS_LITERAL_STRING("_moz_anonclass"), anonclass);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     if (!StringBeginsWith(anonclass, NS_LITERAL_STRING("mozTable")))
       return NS_OK;
@@ -171,7 +171,7 @@ nsHTMLEditor::DoInlineTableEditingAction(nsIDOMElement * aElement)
     nsCOMPtr<nsIDOMElement> tableElement = do_QueryInterface(tableNode);
     PRInt32 rowCount, colCount;
     res = GetTableSize(tableElement, &rowCount, &colCount);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     PRBool hideUI = PR_FALSE;
     PRBool hideResizersWithInlineTableUI = (mResizedObject == tableElement);
@@ -239,9 +239,9 @@ nsHTMLEditor::RefreshInlineTableEditingUI()
   GetElementOrigin(mInlineEditedCell, xCell, yCell);
 
   nsresult res = nsElement->GetOffsetWidth(&wCell);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = nsElement->GetOffsetHeight(&hCell);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   PRInt32 xHoriz = xCell + wCell/2;
   PRInt32 yVert  = yCell + hCell/2;
@@ -250,7 +250,7 @@ nsHTMLEditor::RefreshInlineTableEditingUI()
   nsCOMPtr<nsIDOMElement> tableElement = do_QueryInterface(tableNode);
   PRInt32 rowCount, colCount;
   res = GetTableSize(tableElement, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   SetAnonymousElementPosition(xHoriz-10, yCell-7,  mAddColumnBeforeButton);
 #ifdef DISABLE_TABLE_DELETION
diff --git a/editor/libeditor/html/nsHTMLObjectResizer.cpp b/editor/libeditor/html/nsHTMLObjectResizer.cpp
index 74c3a1de894..93c64074971 100644
--- a/editor/libeditor/html/nsHTMLObjectResizer.cpp
+++ b/editor/libeditor/html/nsHTMLObjectResizer.cpp
@@ -187,7 +187,7 @@ nsHTMLEditor::CreateResizer(nsIDOMElement ** aReturn, PRInt16 aLocation, nsIDOMN
                                         PR_FALSE,
                                         aReturn);
 
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!*aReturn)
     return NS_ERROR_FAILURE;
 
@@ -325,9 +325,9 @@ nsHTMLEditor::RefreshResizers()
                                           mResizedObjectMarginLeft,
                                           mResizedObjectMarginTop);
 
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = SetAllResizersPosition();
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   return SetShadowPosition(mResizingShadow, mResizedObject,
                            mResizedObjectX, mResizedObjectY);
 }
@@ -360,30 +360,30 @@ nsHTMLEditor::ShowResizersInner(nsIDOMElement *aResizedElement)
   // The resizers and the shadow will be anonymous siblings of the element.
   res = CreateResizer(getter_AddRefs(mTopLeftHandle),
                       nsIHTMLObjectResizer::eTopLeft,     parentNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = CreateResizer(getter_AddRefs(mTopHandle),
                       nsIHTMLObjectResizer::eTop,         parentNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = CreateResizer(getter_AddRefs(mTopRightHandle),
                       nsIHTMLObjectResizer::eTopRight,    parentNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   res = CreateResizer(getter_AddRefs(mLeftHandle),
                       nsIHTMLObjectResizer::eLeft,        parentNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = CreateResizer(getter_AddRefs(mRightHandle),
                       nsIHTMLObjectResizer::eRight,       parentNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   res = CreateResizer(getter_AddRefs(mBottomLeftHandle),
                       nsIHTMLObjectResizer::eBottomLeft,  parentNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = CreateResizer(getter_AddRefs(mBottomHandle),
                       nsIHTMLObjectResizer::eBottom,      parentNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = CreateResizer(getter_AddRefs(mBottomRightHandle),
                       nsIHTMLObjectResizer::eBottomRight, parentNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   res = GetPositionAndDimensions(aResizedElement,
                                  mResizedObjectX,
@@ -394,24 +394,24 @@ nsHTMLEditor::ShowResizersInner(nsIDOMElement *aResizedElement)
                                  mResizedObjectBorderTop,
                                  mResizedObjectMarginLeft,
                                  mResizedObjectMarginTop);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // and let's set their absolute positions in the document
   res = SetAllResizersPosition();
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // now, let's create the resizing shadow
   res = CreateShadow(getter_AddRefs(mResizingShadow), parentNode,
                      aResizedElement);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // and set its position
   res = SetShadowPosition(mResizingShadow, mResizedObject,
                           mResizedObjectX, mResizedObjectY);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // and then the resizing info tooltip
   res = CreateResizingInfo(getter_AddRefs(mResizingInfo), parentNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // and listen to the "resize" event on the window first, get the
   // window from the document...
@@ -644,7 +644,7 @@ nsHTMLEditor::MouseDown(PRInt32 aClientX, PRInt32 aClientY,
     if (anonElement) {
       nsAutoString anonclass;
       nsresult res = aTarget->GetAttribute(NS_LITERAL_STRING("_moz_anonclass"), anonclass);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (anonclass.EqualsLiteral("mozResizer")) {
         // and that element is a resizer, let's start resizing!
         aEvent->PreventDefault();
@@ -749,11 +749,11 @@ nsHTMLEditor::SetResizingInfoPosition(PRInt32 aX, PRInt32 aY, PRInt32 aW, PRInt3
 
   nsCOMPtr<nsIDOMNode> textInfo;
   nsresult res = mResizingInfo->GetFirstChild(getter_AddRefs(textInfo));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsCOMPtr<nsIDOMNode> junk;
   if (textInfo) {
     res = mResizingInfo->RemoveChild(textInfo, getter_AddRefs(junk));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     textInfo = nsnull;
     junk = nsnull;
   }
@@ -777,10 +777,10 @@ nsHTMLEditor::SetResizingInfoPosition(PRInt32 aX, PRInt32 aY, PRInt32 aW, PRInt3
 
   nsCOMPtr<nsIDOMText> nodeAsText;
   res = domdoc->CreateTextNode(info, getter_AddRefs(nodeAsText));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   textInfo = do_QueryInterface(nodeAsText);
   res =  mResizingInfo->AppendChild(textInfo, getter_AddRefs(junk));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   PRBool hasClass = PR_FALSE;
   if (NS_SUCCEEDED(mResizingInfo->HasAttribute(NS_LITERAL_STRING("class"), &hasClass )) && hasClass)
@@ -801,9 +801,9 @@ nsHTMLEditor::SetShadowPosition(nsIDOMElement * aShadow,
     nsAutoString imageSource;
     nsresult res = aOriginalObject->GetAttribute(NS_LITERAL_STRING("src"),
                                                 imageSource);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = aShadow->SetAttribute(NS_LITERAL_STRING("src"), imageSource);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return NS_OK;
 }
diff --git a/editor/libeditor/html/nsTableEditor.cpp b/editor/libeditor/html/nsTableEditor.cpp
index 3feac934eaf..86099c0173c 100644
--- a/editor/libeditor/html/nsTableEditor.cpp
+++ b/editor/libeditor/html/nsTableEditor.cpp
@@ -130,13 +130,13 @@ nsHTMLEditor::InsertCell(nsIDOMElement *aCell, PRInt32 aRowSpan, PRInt32 aColSpa
   // And the parent and offsets needed to do an insert
   nsCOMPtr<nsIDOMNode> cellParent;
   nsresult res = aCell->GetParentNode(getter_AddRefs(cellParent));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!cellParent) return NS_ERROR_NULL_POINTER;
 
 
   PRInt32 cellOffset;
   res = GetChildOffset(aCell, cellParent, cellOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMElement> newCell;
   if (aIsHeader)
@@ -207,7 +207,7 @@ nsHTMLEditor::InsertTableCell(PRInt32 aNumber, PRBool aAfter)
                                 getter_AddRefs(curCell), 
                                 getter_AddRefs(cellParent), &cellOffset,
                                 &startRowIndex, &startColIndex);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // Don't fail if no cell found
   if (!curCell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
@@ -218,7 +218,7 @@ nsHTMLEditor::InsertTableCell(PRInt32 aNumber, PRBool aAfter)
                       getter_AddRefs(curCell),
                       &curStartRowIndex, &curStartColIndex, &rowSpan, &colSpan,
                       &actualRowSpan, &actualColSpan, &isSelected);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!curCell) return NS_ERROR_FAILURE;
   PRInt32 newCellIndex = aAfter ? (startColIndex+colSpan) : startColIndex;
   //We control selection resetting after the insert...
@@ -253,12 +253,12 @@ nsHTMLEditor::GetFirstRow(nsIDOMElement* aTableElement, nsIDOMNode** aRowNode)
 
   nsCOMPtr<nsIDOMElement> tableElement;
   nsresult res = GetElementOrParentByTagName(NS_LITERAL_STRING("table"), aTableElement, getter_AddRefs(tableElement));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!tableElement) return NS_ERROR_NULL_POINTER;
 
   nsCOMPtr<nsIDOMNode> tableChild;
   res = tableElement->GetFirstChild(getter_AddRefs(tableChild));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   while (tableChild)
   {
@@ -281,14 +281,14 @@ nsHTMLEditor::GetFirstRow(nsIDOMElement* aTableElement, nsIDOMNode** aRowNode)
       {
         nsCOMPtr<nsIDOMNode> rowNode;
         res = tableChild->GetFirstChild(getter_AddRefs(rowNode));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         
         // We can encounter textnodes here -- must find a row
         while (rowNode && !nsHTMLEditUtils::IsTableRow(rowNode))
         {
           nsCOMPtr<nsIDOMNode> nextNode;
           res = rowNode->GetNextSibling(getter_AddRefs(nextNode));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
 
           rowNode = nextNode;
         }
@@ -306,7 +306,7 @@ nsHTMLEditor::GetFirstRow(nsIDOMElement* aTableElement, nsIDOMNode** aRowNode)
     // Look in next table child
     nsCOMPtr<nsIDOMNode> nextChild;
     res = tableChild->GetNextSibling(getter_AddRefs(nextChild));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     tableChild = nextChild;
   };
@@ -328,7 +328,7 @@ nsHTMLEditor::GetNextRow(nsIDOMNode* aCurrentRowNode, nsIDOMNode **aRowNode)
   
   nsCOMPtr<nsIDOMNode> nextRow;
   nsresult res = aCurrentRowNode->GetNextSibling(getter_AddRefs(nextRow));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMNode> nextNode;
 
@@ -336,7 +336,7 @@ nsHTMLEditor::GetNextRow(nsIDOMNode* aCurrentRowNode, nsIDOMNode **aRowNode)
   while (nextRow && !nsHTMLEditUtils::IsTableRow(nextRow))
   {
     res = nextRow->GetNextSibling(getter_AddRefs(nextNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   
     nextRow = nextNode;
   }
@@ -350,23 +350,23 @@ nsHTMLEditor::GetNextRow(nsIDOMNode* aCurrentRowNode, nsIDOMNode **aRowNode)
   // No row found, search for rows in other table sections
   nsCOMPtr<nsIDOMNode> rowParent;
   res = aCurrentRowNode->GetParentNode(getter_AddRefs(rowParent));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!rowParent) return NS_ERROR_NULL_POINTER;
 
   nsCOMPtr<nsIDOMNode> parentSibling;
   res = rowParent->GetNextSibling(getter_AddRefs(parentSibling));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   while (parentSibling)
   {
     res = parentSibling->GetFirstChild(getter_AddRefs(nextRow));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   
     // We can encounter textnodes here -- must find a row
     while (nextRow && !nsHTMLEditUtils::IsTableRow(nextRow))
     {
       res = nextRow->GetNextSibling(getter_AddRefs(nextNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       nextRow = nextNode;
     }
@@ -383,7 +383,7 @@ nsHTMLEditor::GetNextRow(nsIDOMNode* aCurrentRowNode, nsIDOMNode **aRowNode)
     //  or first child of section is not a row (bad HTML or more "_moz_text" nodes!)
     // So look for another section sibling
     res = parentSibling->GetNextSibling(getter_AddRefs(nextNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     parentSibling = nextNode;
   }
@@ -402,14 +402,14 @@ nsHTMLEditor::GetLastCellInRow(nsIDOMNode* aRowNode, nsIDOMNode** aCellNode)
 
   nsCOMPtr<nsIDOMNode> rowChild;
   nsresult res = aRowNode->GetLastChild(getter_AddRefs(rowChild));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   while (rowChild && !nsHTMLEditUtils::IsTableCell(rowChild))
   {
     // Skip over textnodes
     nsCOMPtr<nsIDOMNode> previousChild;
     res = rowChild->GetPreviousSibling(getter_AddRefs(previousChild));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     rowChild = previousChild;
   };
@@ -435,7 +435,7 @@ nsHTMLEditor::InsertTableColumn(PRInt32 aNumber, PRBool aAfter)
                                 getter_AddRefs(curCell), 
                                 nsnull, nsnull,
                                 &startRowIndex, &startColIndex);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // Don't fail if no cell found
   if (!curCell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
@@ -447,7 +447,7 @@ nsHTMLEditor::InsertTableColumn(PRInt32 aNumber, PRBool aAfter)
                       &curStartRowIndex, &curStartColIndex,
                       &rowSpan, &colSpan, 
                       &actualRowSpan, &actualColSpan, &isSelected);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!curCell) return NS_ERROR_FAILURE;
 
   nsAutoEditBatch beginBatching(this);
@@ -468,7 +468,7 @@ nsHTMLEditor::InsertTableColumn(PRInt32 aNumber, PRBool aAfter)
    
   PRInt32 rowCount, colCount, rowIndex;
   res = GetTableSize(table, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   //We reset caret in destructor...
   nsSetSelectionAfterTableEdit setCaret(this, table, startRowIndex, startColIndex, ePreviousRow, PR_FALSE);
@@ -497,7 +497,7 @@ nsHTMLEditor::InsertTableColumn(PRInt32 aNumber, PRBool aAfter)
                           &curStartRowIndex, &curStartColIndex,
                           &rowSpan, &colSpan, 
                           &actualRowSpan, &actualColSpan, &isSelected);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       // Don't fail entire process if we fail to find a cell
       //  (may fail just in particular rows with < adequate cells per row)
@@ -529,13 +529,13 @@ nsHTMLEditor::InsertTableColumn(PRInt32 aNumber, PRBool aAfter)
         res = GetNextRow(rowNode.get(), getter_AddRefs(nextRow));
         rowNode = nextRow;
       }
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       if (rowNode)
       {
         nsCOMPtr<nsIDOMNode> lastCell;
         res = GetLastCellInRow(rowNode, getter_AddRefs(lastCell));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (!lastCell) return NS_ERROR_FAILURE;
 
         curCell = do_QueryInterface(lastCell);
@@ -568,7 +568,7 @@ nsHTMLEditor::InsertTableRow(PRInt32 aNumber, PRBool aAfter)
                                 getter_AddRefs(curCell), 
                                 nsnull, nsnull, 
                                 &startRowIndex, &startColIndex);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // Don't fail if no cell found
   if (!curCell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
@@ -580,12 +580,12 @@ nsHTMLEditor::InsertTableRow(PRInt32 aNumber, PRBool aAfter)
                       &curStartRowIndex, &curStartColIndex,
                       &rowSpan, &colSpan, 
                       &actualRowSpan, &actualColSpan, &isSelected);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!curCell) return NS_ERROR_FAILURE;
   
   PRInt32 rowCount, colCount;
   res = GetTableSize(table, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsAutoEditBatch beginBatching(this);
   // Prevent auto insertion of BR in new cell until we're done
@@ -690,14 +690,14 @@ nsHTMLEditor::InsertTableRow(PRInt32 aNumber, PRBool aAfter)
     {
       nsCOMPtr<nsIDOMElement> parentRow;
       res = GetElementOrParentByTagName(trStr, cellForRowParent, getter_AddRefs(parentRow));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!parentRow) return NS_ERROR_NULL_POINTER;
 
       parentRow->GetParentNode(getter_AddRefs(parentOfRow));
       if (!parentOfRow) return NS_ERROR_NULL_POINTER;
 
       res = GetChildOffset(parentRow, parentOfRow, newRowOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       
       // Adjust for when adding past the end 
       if (aAfter && startRowIndex >= rowCount)
@@ -719,18 +719,18 @@ nsHTMLEditor::InsertTableRow(PRInt32 aNumber, PRBool aAfter)
         {
           nsCOMPtr<nsIDOMElement> newCell;
           res = CreateElementWithDefaults(NS_LITERAL_STRING("td"), getter_AddRefs(newCell));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           if (!newCell) return NS_ERROR_FAILURE;
 
           // Don't use transaction system yet! (not until entire row is inserted)
           nsCOMPtr<nsIDOMNode>resultNode;
           res = newRow->AppendChild(newCell, getter_AddRefs(resultNode));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         // Use transaction system to insert the entire row+cells
         // (Note that rows are inserted at same childoffset each time)
         res = InsertNode(newRow, parentOfRow, newRowOffset);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
   }
@@ -749,7 +749,7 @@ nsHTMLEditor::DeleteTable2(nsIDOMElement *aTable, nsISelection *aSelection)
   nsresult res = ClearSelection();
   if (NS_SUCCEEDED(res))
     res = AppendNodeToSelectionAsRange(aTable);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   return DeleteSelection(nsIEditor::eNext);
 }
@@ -763,7 +763,7 @@ nsHTMLEditor::DeleteTable()
                                 getter_AddRefs(table), 
                                 nsnull, nsnull, nsnull, nsnull, nsnull);
     
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsAutoEditBatch beginBatching(this);
   return DeleteTable2(table, selection);
@@ -784,7 +784,7 @@ nsHTMLEditor::DeleteTableCell(PRInt32 aNumber)
                          nsnull, nsnull,
                          &startRowIndex, &startColIndex);
 
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // Don't fail if we didn't find a table or cell
   if (!table || !cell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
@@ -795,11 +795,11 @@ nsHTMLEditor::DeleteTableCell(PRInt32 aNumber)
   nsCOMPtr<nsIDOMElement> firstCell;
   nsCOMPtr<nsIDOMRange> range;
   res = GetFirstSelectedCell(getter_AddRefs(range), getter_AddRefs(firstCell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   PRInt32 rangeCount;
   res = selection->GetRangeCount(&rangeCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   if (firstCell && rangeCount > 1)
   {
@@ -809,11 +809,11 @@ nsHTMLEditor::DeleteTableCell(PRInt32 aNumber)
 
     PRInt32 rowCount, colCount;
     res = GetTableSize(table, &rowCount, &colCount);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // Get indexes -- may be different than original cell
     res = GetCellIndexes(cell, &startRowIndex, &startColIndex);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // The setCaret object will call SetSelectionAfterTableEdit in it's destructor
     nsSetSelectionAfterTableEdit setCaret(this, table, startRowIndex, startColIndex, ePreviousColumn, PR_FALSE);
@@ -841,14 +841,14 @@ nsHTMLEditor::DeleteTableCell(PRInt32 aNumber)
           while (nextRow == startRowIndex)
           {
             res = GetNextSelectedCell(nsnull, getter_AddRefs(cell));
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
             if (!cell) break;
             res = GetCellIndexes(cell, &nextRow, &startColIndex);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
           // Delete entire row
           res = DeleteRow(table, startRowIndex);          
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
 
           if (cell)
           {
@@ -876,14 +876,14 @@ nsHTMLEditor::DeleteTableCell(PRInt32 aNumber)
             while (nextCol == startColIndex)
             {
               res = GetNextSelectedCell(nsnull, getter_AddRefs(cell));
-              if (NS_FAILED(res)) return res;
+              NS_ENSURE_SUCCESS(res, res);
               if (!cell) break;
               res = GetCellIndexes(cell, &startRowIndex, &nextCol);
-              if (NS_FAILED(res)) return res;
+              NS_ENSURE_SUCCESS(res, res);
             }
             // Delete entire Col
             res = DeleteColumn(table, startColIndex);          
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
             if (cell) 
             {
               // For the next cell, subtract 1 for col. deleted
@@ -898,18 +898,18 @@ nsHTMLEditor::DeleteTableCell(PRInt32 aNumber)
           // First get the next cell to delete
           nsCOMPtr<nsIDOMElement> nextCell;
           res = GetNextSelectedCell(getter_AddRefs(range), getter_AddRefs(nextCell));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
 
           // Then delete the cell
           res = DeleteNode(cell);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           
           // The next cell to delete
           cell = nextCell;
           if (cell)
           {
             res = GetCellIndexes(cell, &startRowIndex, &startColIndex);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
         }
       }
@@ -922,7 +922,7 @@ nsHTMLEditor::DeleteTableCell(PRInt32 aNumber)
                          getter_AddRefs(cell), 
                          nsnull, nsnull,
                          &startRowIndex, &startColIndex);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // Don't fail if no cell found
     if (!cell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
@@ -930,7 +930,7 @@ nsHTMLEditor::DeleteTableCell(PRInt32 aNumber)
     {
       nsCOMPtr<nsIDOMElement> parentRow;
       res = GetElementOrParentByTagName(NS_LITERAL_STRING("tr"), cell, getter_AddRefs(parentRow));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!parentRow) return NS_ERROR_NULL_POINTER;
 
       // We should delete the row instead,
@@ -938,14 +938,14 @@ nsHTMLEditor::DeleteTableCell(PRInt32 aNumber)
       //  so we can delete the entire table
       PRInt32 rowCount, colCount;
       res = GetTableSize(table, &rowCount, &colCount);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       
       if (rowCount == 1)
         return DeleteTable2(table, selection);
     
       // We need to call DeleteTableRow to handle cells with rowspan 
       res = DeleteTableRow(1);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     } 
     else
     {
@@ -957,7 +957,7 @@ nsHTMLEditor::DeleteTableCell(PRInt32 aNumber)
 
       res = DeleteNode(cell);
       // If we fail, don't try to delete any more cells???
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   return NS_OK;
@@ -976,7 +976,7 @@ nsHTMLEditor::DeleteTableCellContents()
                        getter_AddRefs(cell), 
                        nsnull, nsnull,
                        &startRowIndex, &startColIndex);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // Don't fail if no cell found
   if (!cell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
@@ -991,14 +991,14 @@ nsHTMLEditor::DeleteTableCellContents()
   nsCOMPtr<nsIDOMElement> firstCell;
   nsCOMPtr<nsIDOMRange> range;
   res = GetFirstSelectedCell(getter_AddRefs(range), getter_AddRefs(firstCell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
 
   if (firstCell)
   {
     cell = firstCell;
     res = GetCellIndexes(cell, &startRowIndex, &startColIndex);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   nsSetSelectionAfterTableEdit setCaret(this, table, startRowIndex, startColIndex, ePreviousColumn, PR_FALSE);
@@ -1010,7 +1010,7 @@ nsHTMLEditor::DeleteTableCellContents()
     {
       // We doing a selected cells, so do all of them
       res = GetNextSelectedCell(nsnull, getter_AddRefs(cell));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     else
       cell = nsnull;
@@ -1034,7 +1034,7 @@ nsHTMLEditor::DeleteCellContents(nsIDOMElement *aCell)
   {
     aCell->GetLastChild(getter_AddRefs(child));
     nsresult res = DeleteNode(child);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     aCell->HasChildNodes(&hasChild);
   }
   return NS_OK;
@@ -1052,12 +1052,12 @@ nsHTMLEditor::DeleteTableColumn(PRInt32 aNumber)
                                 getter_AddRefs(cell), 
                                 nsnull, nsnull,
                                 &startRowIndex, &startColIndex);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // Don't fail if no cell found
   if (!table || !cell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
   res = GetTableSize(table, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // Shortcut the case of deleting all columns in table
   if(startColIndex == 0 && aNumber >= colCount)
@@ -1074,17 +1074,17 @@ nsHTMLEditor::DeleteTableColumn(PRInt32 aNumber)
   nsCOMPtr<nsIDOMElement> firstCell;
   nsCOMPtr<nsIDOMRange> range;
   res = GetFirstSelectedCell(getter_AddRefs(range), getter_AddRefs(firstCell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   PRInt32 rangeCount;
   res = selection->GetRangeCount(&rangeCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   if (firstCell && rangeCount > 1)
   {
     // Fetch indexes again - may be different for selected cells
     res = GetCellIndexes(firstCell, &startRowIndex, &startColIndex);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   //We control selection resetting after the insert...
   nsSetSelectionAfterTableEdit setCaret(this, table, startRowIndex, startColIndex, ePreviousRow, PR_FALSE);
@@ -1099,7 +1099,7 @@ nsHTMLEditor::DeleteTableColumn(PRInt32 aNumber)
       if (cell != firstCell)
       {
         res = GetCellIndexes(cell, &startRowIndex, &startColIndex);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       // Find the next cell in a different column
       // to continue after we delete this column
@@ -1107,19 +1107,19 @@ nsHTMLEditor::DeleteTableColumn(PRInt32 aNumber)
       while (nextCol == startColIndex)
       {
         res = GetNextSelectedCell(getter_AddRefs(range), getter_AddRefs(cell));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (!cell) break;
         res = GetCellIndexes(cell, &startRowIndex, &nextCol);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       res = DeleteColumn(table, startColIndex);          
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   else for (PRInt32 i = 0; i < aNumber; i++)
   {
     res = DeleteColumn(table, startColIndex);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return NS_OK;
 }
@@ -1141,7 +1141,7 @@ nsHTMLEditor::DeleteColumn(nsIDOMElement *aTable, PRInt32 aColIndex)
                         &startRowIndex, &startColIndex, &rowSpan, &colSpan, 
                         &actualRowSpan, &actualColSpan, &isSelected);
 
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     if (cell)
     {
@@ -1174,7 +1174,7 @@ nsHTMLEditor::DeleteColumn(nsIDOMElement *aTable, PRInt32 aColIndex)
           // Only 1 cell in row - delete the row
           nsCOMPtr<nsIDOMElement> parentRow;
           res = GetElementOrParentByTagName(NS_LITERAL_STRING("tr"), cell, getter_AddRefs(parentRow));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           if(!parentRow) return NS_ERROR_NULL_POINTER;
 
           //  But first check if its the only row left
@@ -1182,13 +1182,13 @@ nsHTMLEditor::DeleteColumn(nsIDOMElement *aTable, PRInt32 aColIndex)
           //  (This should never happen but it's the safe thing to do)
           PRInt32 rowCount, colCount;
           res = GetTableSize(aTable, &rowCount, &colCount);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
 
           if (rowCount == 1)
           {
             nsCOMPtr<nsISelection> selection;
             res = GetSelection(getter_AddRefs(selection));
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
             if (!selection) return NS_ERROR_FAILURE;
             return DeleteTable2(aTable, selection);
           }
@@ -1196,7 +1196,7 @@ nsHTMLEditor::DeleteColumn(nsIDOMElement *aTable, PRInt32 aColIndex)
           // Delete the row by placing caret in cell we were to delete
           // We need to call DeleteTableRow to handle cells with rowspan 
           res = DeleteRow(aTable, startRowIndex);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
 
           // Note that we don't incremenet rowIndex
           // since a row was deleted and "next" 
@@ -1206,7 +1206,7 @@ nsHTMLEditor::DeleteColumn(nsIDOMElement *aTable, PRInt32 aColIndex)
         {
           // A more "normal" deletion
           res = DeleteNode(cell);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
 
           //Skip over any rows spanned by this cell
           rowIndex += actualRowSpan;
@@ -1231,12 +1231,12 @@ nsHTMLEditor::DeleteTableRow(PRInt32 aNumber)
                                  getter_AddRefs(cell), 
                                  nsnull, nsnull,
                                  &startRowIndex, &startColIndex);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // Don't fail if no cell found
   if (!cell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
   res = GetTableSize(table, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // Shortcut the case of deleting all rows in table
   if(startRowIndex == 0 && aNumber >= rowCount)
@@ -1249,17 +1249,17 @@ nsHTMLEditor::DeleteTableRow(PRInt32 aNumber)
   nsCOMPtr<nsIDOMElement> firstCell;
   nsCOMPtr<nsIDOMRange> range;
   res = GetFirstSelectedCell(getter_AddRefs(range), getter_AddRefs(firstCell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   PRInt32 rangeCount;
   res = selection->GetRangeCount(&rangeCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   if (firstCell && rangeCount > 1)
   {
     // Fetch indexes again - may be different for selected cells
     res = GetCellIndexes(firstCell, &startRowIndex, &startColIndex);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   //We control selection resetting after the insert...
@@ -1277,7 +1277,7 @@ nsHTMLEditor::DeleteTableRow(PRInt32 aNumber)
       if (cell != firstCell)
       {
         res = GetCellIndexes(cell, &startRowIndex, &startColIndex);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       // Find the next cell in a different row
       // to continue after we delete this row
@@ -1285,14 +1285,14 @@ nsHTMLEditor::DeleteTableRow(PRInt32 aNumber)
       while (nextRow == startRowIndex)
       {
         res = GetNextSelectedCell(getter_AddRefs(range), getter_AddRefs(cell));
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
         if (!cell) break;
         res = GetCellIndexes(cell, &nextRow, &startColIndex);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       // Delete entire row
       res = DeleteRow(table, startRowIndex);          
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   else
@@ -1309,7 +1309,7 @@ nsHTMLEditor::DeleteTableRow(PRInt32 aNumber)
     
       // Check if there's a cell in the "next" row
       res = GetCellAt(table, startRowIndex, startColIndex, getter_AddRefs(cell));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if(!cell)
         break;
     }
@@ -1377,7 +1377,7 @@ nsHTMLEditor::DeleteRow(nsIDOMElement *aTable, PRInt32 aRowIndex)
           res = SplitCellIntoRows(aTable, startRowIndex, startColIndex,
                                   aRowIndex - startRowIndex + 1, // The row above the row to insert new cell into
                                   actualRowSpan - 1, nsnull);    // Span remaining below
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         if (!cellInDeleteRow)
           cellInDeleteRow = cell; // Reference cell to find row to delete
@@ -1394,12 +1394,12 @@ nsHTMLEditor::DeleteRow(nsIDOMElement *aTable, PRInt32 aRowIndex)
   // Delete the entire row
   nsCOMPtr<nsIDOMElement> parentRow;
   res = GetElementOrParentByTagName(NS_LITERAL_STRING("tr"), cellInDeleteRow, getter_AddRefs(parentRow));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   if (parentRow)
   {
     res = DeleteNode(parentRow);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   // Now we can set new rowspans for cells stored above  
@@ -1409,7 +1409,7 @@ nsHTMLEditor::DeleteRow(nsIDOMElement *aTable, PRInt32 aRowIndex)
     if (cellPtr)
     {
       res = SetRowSpan(cellPtr, newSpanList[i]);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   return NS_OK;
@@ -1422,7 +1422,7 @@ nsHTMLEditor::SelectTable()
   nsCOMPtr<nsIDOMElement> table;
   nsresult res = NS_ERROR_FAILURE;
   res = GetElementOrParentByTagName(NS_LITERAL_STRING("table"), nsnull, getter_AddRefs(table));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // Don't fail if we didn't find a table
   if (!table) return NS_OK;
 
@@ -1438,7 +1438,7 @@ nsHTMLEditor::SelectTableCell()
 {
   nsCOMPtr<nsIDOMElement> cell;
   nsresult res = GetElementOrParentByTagName(NS_LITERAL_STRING("td"), nsnull, getter_AddRefs(cell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!cell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
   res = ClearSelection();
@@ -1455,18 +1455,18 @@ nsHTMLEditor::SelectBlockOfCells(nsIDOMElement *aStartCell, nsIDOMElement *aEndC
   
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_FAILURE;
 
   NS_NAMED_LITERAL_STRING(tableStr, "table");
   nsCOMPtr<nsIDOMElement> table;
   res = GetElementOrParentByTagName(tableStr, aStartCell, getter_AddRefs(table));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!table) return NS_ERROR_FAILURE;
 
   nsCOMPtr<nsIDOMElement> endTable;
   res = GetElementOrParentByTagName(tableStr, aEndCell, getter_AddRefs(endTable));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!endTable) return NS_ERROR_FAILURE;
   
   // We can only select a block if within the same table,
@@ -1497,13 +1497,13 @@ nsHTMLEditor::SelectBlockOfCells(nsIDOMElement *aStartCell, nsIDOMElement *aEndC
   PRInt32 currentRowIndex, currentColIndex;
   nsCOMPtr<nsIDOMRange> range;
   res = GetFirstSelectedCell(getter_AddRefs(range), getter_AddRefs(cell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (res == NS_EDITOR_ELEMENT_NOT_FOUND) return NS_OK;
 
   while (cell)
   {
     res = GetCellIndexes(cell, &currentRowIndex, &currentColIndex);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     if (currentRowIndex < maxRow || currentRowIndex > maxRow || 
         currentColIndex < maxColumn || currentColIndex > maxColumn)
@@ -1513,7 +1513,7 @@ nsHTMLEditor::SelectBlockOfCells(nsIDOMElement *aStartCell, nsIDOMElement *aEndC
       mSelectedCellIndex--;
     }    
     res = GetNextSelectedCell(getter_AddRefs(range), getter_AddRefs(cell));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   PRInt32 rowSpan, colSpan, actualRowSpan, actualColSpan;
@@ -1543,7 +1543,7 @@ nsHTMLEditor::SelectAllTableCells()
 {
   nsCOMPtr<nsIDOMElement> cell;
   nsresult res = GetElementOrParentByTagName(NS_LITERAL_STRING("td"), nsnull, getter_AddRefs(cell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // Don't fail if we didn't find a cell
   if (!cell) return NS_EDITOR_ELEMENT_NOT_FOUND;
@@ -1553,16 +1553,16 @@ nsHTMLEditor::SelectAllTableCells()
   // Get parent table
   nsCOMPtr<nsIDOMElement> table;
   res = GetElementOrParentByTagName(NS_LITERAL_STRING("table"), cell, getter_AddRefs(table));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if(!table) return NS_ERROR_NULL_POINTER;
 
   PRInt32 rowCount, colCount;
   res = GetTableSize(table, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsISelection> selection;
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_FAILURE;
 
   // Suppress nsISelectionListener notification
@@ -1608,7 +1608,7 @@ nsHTMLEditor::SelectTableRow()
 {
   nsCOMPtr<nsIDOMElement> cell;
   nsresult res = GetElementOrParentByTagName(NS_LITERAL_STRING("td"), nsnull, getter_AddRefs(cell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // Don't fail if we didn't find a cell
   if (!cell) return NS_EDITOR_ELEMENT_NOT_FOUND;
@@ -1624,12 +1624,12 @@ nsHTMLEditor::SelectTableRow()
                        getter_AddRefs(cell),
                        nsnull, nsnull,
                        &startRowIndex, &startColIndex);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!table) return NS_ERROR_FAILURE;
   
   PRInt32 rowCount, colCount;
   res = GetTableSize(table, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   //Note: At this point, we could get first and last cells in row,
   //  then call SelectBlockOfCells, but that would take just
@@ -1674,7 +1674,7 @@ nsHTMLEditor::SelectTableColumn()
 {
   nsCOMPtr<nsIDOMElement> cell;
   nsresult res = GetElementOrParentByTagName(NS_LITERAL_STRING("td"), nsnull, getter_AddRefs(cell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // Don't fail if we didn't find a cell
   if (!cell) return NS_EDITOR_ELEMENT_NOT_FOUND;
@@ -1691,12 +1691,12 @@ nsHTMLEditor::SelectTableColumn()
                        getter_AddRefs(cell),
                        nsnull, nsnull,
                        &startRowIndex, &startColIndex);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!table) return NS_ERROR_FAILURE;
 
   PRInt32 rowCount, colCount;
   res = GetTableSize(table, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // Suppress nsISelectionListener notification
   //  until all selection changes are finished
@@ -1744,12 +1744,12 @@ nsHTMLEditor::SplitTableCell()
                                 getter_AddRefs(cell),
                                 nsnull, nsnull,
                                 &startRowIndex, &startColIndex);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if(!table || !cell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
   // We need rowspan and colspan data
   res = GetCellSpansAt(table, startRowIndex, startColIndex, actualRowSpan, actualColSpan);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // Must have some span to split
   if (actualRowSpan <= 1 && actualColSpan <= 1)
@@ -1776,7 +1776,7 @@ nsHTMLEditor::SplitTableCell()
     if (rowSpanBelow > 0)
     {
       res = SplitCellIntoRows(table, rowIndex, startColIndex, 1, rowSpanBelow, getter_AddRefs(newCell));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       CopyCellBackgroundColor(newCell, cell);
     }
     PRInt32 colIndex = startColIndex;
@@ -1784,7 +1784,7 @@ nsHTMLEditor::SplitTableCell()
     for (colSpanAfter = actualColSpan-1; colSpanAfter > 0; colSpanAfter--)
     {
       res = SplitCellIntoColumns(table, rowIndex, colIndex, 1, colSpanAfter, getter_AddRefs(newCell));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       CopyCellBackgroundColor(newCell, cell);
       colIndex++;
     }
@@ -1826,7 +1826,7 @@ nsHTMLEditor::SplitCellIntoColumns(nsIDOMElement *aTable, PRInt32 aRowIndex, PRI
                                &startRowIndex, &startColIndex,
                                &rowSpan, &colSpan, 
                                &actualRowSpan, &actualColSpan, &isSelected);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!cell) return NS_ERROR_NULL_POINTER;
   
   // We can't split!
@@ -1835,13 +1835,13 @@ nsHTMLEditor::SplitCellIntoColumns(nsIDOMElement *aTable, PRInt32 aRowIndex, PRI
 
   // Reduce colspan of cell to split
   res = SetColSpan(cell, aColSpanLeft);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // Insert new cell after using the remaining span
   //  and always get the new cell so we can copy the background color;
   nsCOMPtr<nsIDOMElement> newCell;
   res = InsertCell(cell, actualRowSpan, aColSpanRight, PR_TRUE, PR_FALSE, getter_AddRefs(newCell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (newCell)
   {
     if (aNewCell)
@@ -1869,7 +1869,7 @@ nsHTMLEditor::SplitCellIntoRows(nsIDOMElement *aTable, PRInt32 aRowIndex, PRInt3
                                &startRowIndex, &startColIndex,
                                &rowSpan, &colSpan, 
                                &actualRowSpan, &actualColSpan, &isSelected);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!cell) return NS_ERROR_NULL_POINTER;
   
   // We can't split!
@@ -1878,7 +1878,7 @@ nsHTMLEditor::SplitCellIntoRows(nsIDOMElement *aTable, PRInt32 aRowIndex, PRInt3
 
   PRInt32 rowCount, colCount;
   res = GetTableSize(aTable, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMElement> cell2;
   nsCOMPtr<nsIDOMElement> lastCellFound;
@@ -1948,14 +1948,14 @@ nsHTMLEditor::SplitCellIntoRows(nsIDOMElement *aTable, PRInt32 aRowIndex, PRInt3
 
   // Reduce rowspan of cell to split
   res = SetRowSpan(cell, aRowSpanAbove);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
 
   // Insert new cell after using the remaining span
   //  and always get the new cell so we can copy the background color;
   nsCOMPtr<nsIDOMElement> newCell;
   res = InsertCell(cell2, aRowSpanBelow, actualColSpan, insertAfter, PR_FALSE, getter_AddRefs(newCell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (newCell)
   {
     if (aNewCell)
@@ -1984,7 +1984,7 @@ nsHTMLEditor::SwitchTableCellHeaderType(nsIDOMElement *aSourceCell, nsIDOMElemen
   //  when replacing nodes
   nsCOMPtr<nsISelection>selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_FAILURE;
   nsAutoSelectionReset selectionResetter(selection, this);
 
@@ -1995,7 +1995,7 @@ nsHTMLEditor::SwitchTableCellHeaderType(nsIDOMElement *aSourceCell, nsIDOMElemen
   // This creates new node, moves children, copies attributes (PR_TRUE)
   //   and manages the selection!
   res = ReplaceContainer(aSourceCell, address_of(newNode), newCellType, nsnull, nsnull, PR_TRUE);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!newNode) return NS_ERROR_FAILURE;
 
   // Return the new cell
@@ -2026,7 +2026,7 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
                                 getter_AddRefs(targetCell),
                                 nsnull, nsnull,
                                 &startRowIndex, &startColIndex);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if(!table || !targetCell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
   nsAutoEditBatch beginBatching(this);
@@ -2040,14 +2040,14 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
   nsCOMPtr<nsIDOMElement> firstCell;
   PRInt32 firstRowIndex, firstColIndex;
   res = GetFirstSelectedCellInTable(&firstRowIndex, &firstColIndex, getter_AddRefs(firstCell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   PRBool joinSelectedCells = PR_FALSE;
   if (firstCell)
   {
     nsCOMPtr<nsIDOMElement> secondCell;
     res = GetNextSelectedCell(nsnull, getter_AddRefs(secondCell));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // If only one cell is selected, join with cell to the right
     joinSelectedCells = (secondCell != nsnull);
@@ -2060,12 +2060,12 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
 
     PRInt32 rowCount, colCount;
     res = GetTableSize(table, &rowCount, &colCount);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // Get spans for cell we will merge into
     PRInt32 firstRowSpan, firstColSpan;
     res = GetCellSpansAt( table, firstRowIndex, firstColIndex, firstRowSpan, firstColSpan);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // This defines the last indexes along the "edges"
     //  of the contiguous block of cells, telling us
@@ -2084,7 +2084,7 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
       PRInt32 currentRowCount = rowCount;
       // Be sure each row doesn't have rowspan errors
       res = FixBadRowSpan(table, rowIndex, rowCount);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       // Adjust rowcount by number of rows we removed
       lastRowIndex -= (currentRowCount-rowCount);
 
@@ -2098,7 +2098,7 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
                             &startRowIndex2, &startColIndex2,
                             &rowSpan2, &colSpan2, 
                             &actualRowSpan2, &actualColSpan2, &isSelected2);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
 
         if (isSelected2)
         {
@@ -2186,7 +2186,7 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
                             &startRowIndex2, &startColIndex2,
                             &rowSpan2, &colSpan2, 
                             &actualRowSpan2, &actualColSpan2, &isSelected2);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
 
         // If this is 0, we are past last cell in row, so exit the loop
         if (actualColSpan2 == 0)
@@ -2213,12 +2213,12 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
               {
                 res = SplitCellIntoColumns(table, startRowIndex2, startColIndex2, 
                                            actualColSpan2-extraColSpan, extraColSpan, nsnull);
-                if (NS_FAILED(res)) return res;
+                NS_ENSURE_SUCCESS(res, res);
               }
             }
 
             res = MergeCells(firstCell, cell2, PR_FALSE);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
             
             // Add cell to list to delete
             deleteList.AppendElement(cell2.get());
@@ -2227,7 +2227,7 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
           {
             // Cell is outside join region -- just merge the contents
             res = MergeCells(firstCell, cell2, PR_FALSE);
-            if (NS_FAILED(res)) return res;
+            NS_ENSURE_SUCCESS(res, res);
           }
         }
       }
@@ -2244,25 +2244,25 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
       {
         nsCOMPtr<nsIDOMNode> node = do_QueryInterface(elementPtr);
         res = DeleteNode(node);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     // Cleanup selection: remove ranges where cells were deleted
     nsCOMPtr<nsISelection> selection;
     res = GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!selection) return NS_ERROR_FAILURE;
 
     PRInt32 rangeCount;
     res = selection->GetRangeCount(&rangeCount);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     nsCOMPtr<nsIDOMRange> range;
     PRInt32 i;
     for (i = 0; i < rangeCount; i++)
     {
       res = selection->GetRangeAt(i, getter_AddRefs(range));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (!range) return NS_ERROR_FAILURE;
 
       nsCOMPtr<nsIDOMElement> deletedCell;
@@ -2277,9 +2277,9 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
 
     // Set spans for the cell everthing merged into
     res = SetRowSpan(firstCell, lastRowIndex-firstRowIndex+1);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     res = SetColSpan(firstCell, lastColIndex-firstColIndex+1);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     
     // Fixup disturbances in table layout
@@ -2291,14 +2291,14 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
     res = GetCellDataAt(table, startRowIndex, startColIndex, getter_AddRefs(targetCell),
                         &startRowIndex, &startColIndex, &rowSpan, &colSpan, 
                         &actualRowSpan, &actualColSpan, &isSelected);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!targetCell) return NS_ERROR_NULL_POINTER;
 
     // Get data for cell to the right
     res = GetCellDataAt(table, startRowIndex, startColIndex+actualColSpan, getter_AddRefs(cell2),
                         &startRowIndex2, &startColIndex2, &rowSpan2, &colSpan2, 
                         &actualRowSpan2, &actualColSpan2, &isSelected2);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if(!cell2) return NS_OK; // Don't fail if there's no cell
 
     // sanity check
@@ -2316,7 +2316,7 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
       res = SplitCellIntoRows(table, startRowIndex2, startColIndex2,
                               spanAboveMergedCell+actualRowSpan, 
                               effectiveRowSpan2-actualRowSpan, nsnull);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
 
     // Move contents from cell to the right
@@ -2325,7 +2325,7 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
     res = MergeCells(targetCell, cell2, 
                      (startRowIndex2 == startRowIndex) && 
                      (effectiveRowSpan2 >= actualRowSpan));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     if (effectiveRowSpan2 < actualRowSpan)
     {
@@ -2341,12 +2341,12 @@ nsHTMLEditor::JoinTableCells(PRBool aMergeNonContiguousContents)
       // Cell we merged started in a row above the target cell
       // Reduce rowspan to give room where target cell will extend it's colspan
       res = SetRowSpan(cell2, spanAboveMergedCell);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
 
     // Reset target cell's colspan to encompass cell to the right
     res = SetColSpan(targetCell, actualColSpan+actualColSpan2);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return res;
 }
@@ -2379,15 +2379,15 @@ nsHTMLEditor::MergeCells(nsCOMPtr<nsIDOMElement> aTargetCell,
       // Start inserting just after last child
       PRUint32 len;
       res = childNodes->GetLength(&len);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (len == 1 && IsEmptyCell(aTargetCell))
       {
           // Delete the empty node
           nsCOMPtr<nsIDOMNode> tempNode;
           res = childNodes->Item(0, getter_AddRefs(cellChild));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           res = DeleteNode(cellChild);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
           insertIndex = 0;
       }
       else
@@ -2401,10 +2401,10 @@ nsHTMLEditor::MergeCells(nsCOMPtr<nsIDOMElement> aTargetCell,
     {
       aCellToMerge->GetLastChild(getter_AddRefs(cellChild));
       res = DeleteNode(cellChild);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       res = InsertNode(cellChild, aTargetCell, insertIndex);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       aCellToMerge->HasChildNodes(&hasChild);
     }
@@ -2425,7 +2425,7 @@ nsHTMLEditor::FixBadRowSpan(nsIDOMElement *aTable, PRInt32 aRowIndex, PRInt32& a
 
   PRInt32 rowCount, colCount;
   nsresult res = GetTableSize(aTable, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMElement>cell;
   PRInt32 startRowIndex, startColIndex, rowSpan, colSpan, actualRowSpan, actualColSpan;
@@ -2483,7 +2483,7 @@ nsHTMLEditor::FixBadColSpan(nsIDOMElement *aTable, PRInt32 aColIndex, PRInt32& a
 
   PRInt32 rowCount, colCount;
   nsresult res = GetTableSize(aTable, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMElement> cell;
   PRInt32 startRowIndex, startColIndex, rowSpan, colSpan, actualRowSpan, actualColSpan;
@@ -2539,18 +2539,18 @@ nsHTMLEditor::NormalizeTable(nsIDOMElement *aTable)
 {
   nsCOMPtr<nsISelection>selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_FAILURE;
 
   nsCOMPtr<nsIDOMElement> table;
   res = GetElementOrParentByTagName(NS_LITERAL_STRING("table"), aTable, getter_AddRefs(table));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // Don't fail if we didn't find a table
   if (!table)         return NS_OK;
 
   PRInt32 rowCount, colCount, rowIndex, colIndex;
   res = GetTableSize(table, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // Save current selection
   nsAutoSelectionReset selectionResetter(selection, this);
@@ -2567,13 +2567,13 @@ nsHTMLEditor::NormalizeTable(nsIDOMElement *aTable)
   for(rowIndex = 0; rowIndex < rowCount; rowIndex++)
   {
     res = FixBadRowSpan(table, rowIndex, rowCount);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   // and same for colspans
   for(colIndex = 0; colIndex < colCount; colIndex++)
   {
     res = FixBadColSpan(table, colIndex, colCount);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   // Fill in missing cellmap locations with empty cells
@@ -2600,7 +2600,7 @@ nsHTMLEditor::NormalizeTable(nsIDOMElement *aTable)
         {
           // Insert a new cell after (PR_TRUE), and return the new cell to us
           res = InsertCell(previousCellInRow, 1, 1, PR_TRUE, PR_FALSE, getter_AddRefs(cell));
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
 
           // Set this so we use returned new "cell" to set previousCellInRow below
           if(cell)
@@ -2690,7 +2690,7 @@ PRBool nsHTMLEditor::GetNumberOfCellsInRow(nsIDOMElement* aTable, PRInt32 rowInd
     res = GetCellDataAt(aTable, rowIndex, colIndex, getter_AddRefs(cell),
                         &startRowIndex, &startColIndex, &rowSpan, &colSpan, 
                         &actualRowSpan, &actualColSpan, &isSelected);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (cell)
     {
       // Only count cells that start in row we are working with
@@ -2723,13 +2723,13 @@ nsHTMLEditor::GetTableSize(nsIDOMElement *aTable,
   nsCOMPtr<nsIDOMElement> table;
   // Get the selected talbe or the table enclosing the selection anchor
   res = GetElementOrParentByTagName(NS_LITERAL_STRING("table"), aTable, getter_AddRefs(table));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!table)         return NS_ERROR_FAILURE;
   
   // frames are not ref counted, so don't use an nsCOMPtr
   nsITableLayout *tableLayoutObject;
   res = GetTableLayoutObject(table.get(), &tableLayoutObject);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!tableLayoutObject)
     return NS_ERROR_FAILURE;
 
@@ -2769,7 +2769,7 @@ nsHTMLEditor::GetCellDataAt(nsIDOMElement* aTable, PRInt32 aRowIndex,
     // Get the selected table or the table enclosing the selection anchor
     nsCOMPtr<nsIDOMElement> table;
     res = GetElementOrParentByTagName(NS_LITERAL_STRING("table"), nsnull, getter_AddRefs(table));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (table)
       aTable = table;
     else
@@ -2779,7 +2779,7 @@ nsHTMLEditor::GetCellDataAt(nsIDOMElement* aTable, PRInt32 aRowIndex,
   // frames are not ref counted, so don't use an nsCOMPtr
   nsITableLayout *tableLayoutObject;
   res = GetTableLayoutObject(aTable, &tableLayoutObject);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!tableLayoutObject) return NS_ERROR_FAILURE;
 
   // Note that this returns NS_TABLELAYOUT_CELL_NOT_FOUND when
@@ -2843,7 +2843,7 @@ nsHTMLEditor::GetCellContext(nsISelection **aSelection,
 
   nsCOMPtr <nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_FAILURE;
 
   if (aSelection)
@@ -2869,7 +2869,7 @@ nsHTMLEditor::GetCellContext(nsISelection **aSelection,
     nsAutoString tagName;
     res = GetSelectedOrParentTableElement(tagName, &selectedCount,
                                           getter_AddRefs(cellOrTableElement));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (tagName.EqualsLiteral("table"))
     {
       // We have a selected table, not a cell
@@ -2894,7 +2894,7 @@ nsHTMLEditor::GetCellContext(nsISelection **aSelection,
 
   // Get containing table
   res = GetElementOrParentByTagName(NS_LITERAL_STRING("table"), cell, getter_AddRefs(table));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // Cell must be in a table, so fail if not found
   if (!table) return NS_ERROR_FAILURE;
   if (aTable)
@@ -2918,7 +2918,7 @@ nsHTMLEditor::GetCellContext(nsISelection **aSelection,
     nsCOMPtr <nsIDOMNode> cellParent;
     // Get the immediate parent of the cell
     res = cell->GetParentNode(getter_AddRefs(cellParent));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // Cell has to have a parent, so fail if not found
     if (!cellParent) return NS_ERROR_FAILURE;
 
@@ -2943,12 +2943,12 @@ nsHTMLEditor::GetCellFromRange(nsIDOMRange *aRange, nsIDOMElement **aCell)
 
   nsCOMPtr<nsIDOMNode> startParent;
   nsresult res = aRange->GetStartContainer(getter_AddRefs(startParent));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!startParent) return NS_ERROR_FAILURE;
 
   PRInt32 startOffset;
   res = aRange->GetStartOffset(&startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMNode> childNode = GetChildAt(startParent, startOffset);
   // This means selection is probably at a text node (or end of doc?)
@@ -2956,12 +2956,12 @@ nsHTMLEditor::GetCellFromRange(nsIDOMRange *aRange, nsIDOMElement **aCell)
 
   nsCOMPtr<nsIDOMNode> endParent;
   res = aRange->GetEndContainer(getter_AddRefs(endParent));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!startParent) return NS_ERROR_FAILURE;
 
   PRInt32 endOffset;
   res = aRange->GetEndOffset(&endOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // If a cell is deleted, the range is collapse
   //   (startOffset == endOffset)
@@ -2989,12 +2989,12 @@ nsHTMLEditor::GetFirstSelectedCell(nsIDOMRange **aRange, nsIDOMElement **aCell)
 
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_FAILURE;
 
   nsCOMPtr<nsIDOMRange> range;
   res = selection->GetRangeAt(0, getter_AddRefs(range));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!range) return NS_ERROR_FAILURE;
 
   mSelectedCellIndex = 0;
@@ -3002,7 +3002,7 @@ nsHTMLEditor::GetFirstSelectedCell(nsIDOMRange **aRange, nsIDOMElement **aCell)
   res = GetCellFromRange(range, aCell);
   // Failure here probably means selection is in a text node,
   //  so there's no selected cell
-  if (NS_FAILED(res)) return NS_EDITOR_ELEMENT_NOT_FOUND;
+  NS_ENSURE_SUCCESS(res, NS_EDITOR_ELEMENT_NOT_FOUND);
   // No cell means range was collapsed (cell was deleted)
   if (!*aCell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
@@ -3027,12 +3027,12 @@ nsHTMLEditor::GetNextSelectedCell(nsIDOMRange **aRange, nsIDOMElement **aCell)
 
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_FAILURE;
 
   PRInt32 rangeCount;
   res = selection->GetRangeCount(&rangeCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // Don't even try if index exceeds range count
   if (mSelectedCellIndex >= rangeCount) 
@@ -3043,12 +3043,12 @@ nsHTMLEditor::GetNextSelectedCell(nsIDOMRange **aRange, nsIDOMElement **aCell)
   for (; mSelectedCellIndex < rangeCount; mSelectedCellIndex++)
   {
     res = selection->GetRangeAt(mSelectedCellIndex, getter_AddRefs(range));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!range) return NS_ERROR_FAILURE;
 
     res = GetCellFromRange(range, aCell);
     // Failure here means the range doesn't contain a cell
-    if (NS_FAILED(res)) return NS_EDITOR_ELEMENT_NOT_FOUND;
+    NS_ENSURE_SUCCESS(res, NS_EDITOR_ELEMENT_NOT_FOUND);
     
     // We found a selected cell
     if (*aCell) break;
@@ -3086,7 +3086,7 @@ nsHTMLEditor::GetFirstSelectedCellInTable(PRInt32 *aRowIndex, PRInt32 *aColIndex
 
   nsCOMPtr<nsIDOMElement> cell;
   nsresult res = GetFirstSelectedCell(nsnull, getter_AddRefs(cell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!cell) return NS_EDITOR_ELEMENT_NOT_FOUND;
 
   *aCell = cell.get();
@@ -3117,7 +3117,7 @@ nsHTMLEditor::SetSelectionAfterTableEdit(nsIDOMElement* aTable, PRInt32 aRow, PR
 
   nsCOMPtr<nsISelection>selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   if (!selection)
   {
@@ -3213,13 +3213,13 @@ nsHTMLEditor::GetSelectedOrParentTableElement(nsAString& aTagName,
 
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_FAILURE;
 
   // Try to get the first selected cell
   nsCOMPtr<nsIDOMElement> tableOrCellElement;
   res = GetFirstSelectedCell(nsnull, getter_AddRefs(tableOrCellElement));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   NS_NAMED_LITERAL_STRING(tdName, "td");
 
@@ -3228,7 +3228,7 @@ nsHTMLEditor::GetSelectedOrParentTableElement(nsAString& aTagName,
       // Each cell is in its own selection range,
       //  so count signals multiple-cell selection
       res = selection->GetRangeCount(aSelectedCount);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       aTagName = tdName;
   }
   else
@@ -3248,7 +3248,7 @@ nsHTMLEditor::GetSelectedOrParentTableElement(nsAString& aTagName,
     {
       PRInt32 anchorOffset;
       res = selection->GetAnchorOffset(&anchorOffset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       selectedNode = GetChildAt(anchorNode, anchorOffset);
       if (!selectedNode)
       {
@@ -3267,7 +3267,7 @@ nsHTMLEditor::GetSelectedOrParentTableElement(nsAString& aTagName,
           // Each cell is in its own selection range,
           //  so count signals multiple-cell selection
           res = selection->GetRangeCount(aSelectedCount);
-          if (NS_FAILED(res)) return res;
+          NS_ENSURE_SUCCESS(res, res);
         }
         else if (atom == nsEditProperty::table)
         {
@@ -3311,16 +3311,16 @@ nsHTMLEditor::GetSelectedCellsType(nsIDOMElement *aElement, PRUint32 *aSelection
   nsCOMPtr<nsIDOMElement> table;
 
   nsresult res = GetElementOrParentByTagName(NS_LITERAL_STRING("table"), aElement, getter_AddRefs(table));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   PRInt32 rowCount, colCount;
   res = GetTableSize(table, &rowCount, &colCount);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // Traverse all selected cells 
   nsCOMPtr<nsIDOMElement> selectedCell;
   res = GetFirstSelectedCell(nsnull, getter_AddRefs(selectedCell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (res == NS_EDITOR_ELEMENT_NOT_FOUND) return NS_OK;
   
   // We have at least one selected cell, so set return value
@@ -3398,7 +3398,7 @@ nsHTMLEditor::AllCellsInRowSelected(nsIDOMElement *aTable, PRInt32 aRowIndex, PR
                                  &rowSpan, &colSpan,
                                  &actualRowSpan, &actualColSpan, &isSelected);
  
-    if (NS_FAILED(res)) return PR_FALSE;
+    NS_ENSURE_SUCCESS(res, PR_FALSE);
     // If no cell, we may have a "ragged" right edge,
     //   so return TRUE only if we already found a cell in the row
     if (!cell) return (col > 0) ? PR_TRUE : PR_FALSE;
@@ -3428,7 +3428,7 @@ nsHTMLEditor::AllCellsInColumnSelected(nsIDOMElement *aTable, PRInt32 aColIndex,
                                  &rowSpan, &colSpan,
                                  &actualRowSpan, &actualColSpan, &isSelected);
     
-    if (NS_FAILED(res)) return PR_FALSE;
+    NS_ENSURE_SUCCESS(res, PR_FALSE);
     // If no cell, we must have a "ragged" right edge on the last column
     //   so return TRUE only if we already found a cell in the row
     if (!cell) return (row > 0) ? PR_TRUE : PR_FALSE;
@@ -3447,13 +3447,13 @@ nsHTMLEditor::IsEmptyCell(nsIDOMElement *aCell)
 
   // Check if target only contains empty text node or <br>
   nsresult res = aCell->GetFirstChild(getter_AddRefs(cellChild));
-  if (NS_FAILED(res)) return PR_FALSE;
+  NS_ENSURE_SUCCESS(res, PR_FALSE);
 
   if (cellChild)
   {
     nsCOMPtr<nsIDOMNode> nextChild;
     res = cellChild->GetNextSibling(getter_AddRefs(nextChild));
-    if (NS_FAILED(res)) return PR_FALSE;
+    NS_ENSURE_SUCCESS(res, PR_FALSE);
     if (!nextChild)
     {
       // We insert a single break into a cell by default
@@ -3463,7 +3463,7 @@ nsHTMLEditor::IsEmptyCell(nsIDOMElement *aCell)
       if (!isEmpty)
       {
         res = IsEmptyNode(cellChild, &isEmpty, PR_FALSE, PR_FALSE);
-        if (NS_FAILED(res)) return PR_FALSE;
+        NS_ENSURE_SUCCESS(res, PR_FALSE);
       }
 
       return isEmpty;
diff --git a/editor/libeditor/text/nsPlaintextDataTransfer.cpp b/editor/libeditor/text/nsPlaintextDataTransfer.cpp
index bff9bef8e04..08988b721ff 100644
--- a/editor/libeditor/text/nsPlaintextDataTransfer.cpp
+++ b/editor/libeditor/text/nsPlaintextDataTransfer.cpp
@@ -158,7 +158,7 @@ NS_IMETHODIMP nsPlaintextEditor::InsertFromDrop(nsIDOMEvent* aDropEvent)
   nsresult rv;
   nsCOMPtr<nsIDragService> dragService = 
            do_GetService("@mozilla.org/widget/dragservice;1", &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsIDragSession> dragSession;
   dragService->GetCurrentSession(getter_AddRefs(dragSession));
@@ -167,17 +167,17 @@ NS_IMETHODIMP nsPlaintextEditor::InsertFromDrop(nsIDOMEvent* aDropEvent)
   // Current doc is destination
   nsCOMPtr<nsIDOMDocument> destdomdoc; 
   rv = GetDocument(getter_AddRefs(destdomdoc)); 
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // Get the nsITransferable interface for getting the data from the drop
   nsCOMPtr<nsITransferable> trans;
   rv = PrepareTransferable(getter_AddRefs(trans));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!trans) return NS_OK;  // NS_ERROR_FAILURE; SHOULD WE FAIL?
 
   PRUint32 numItems = 0; 
   rv = dragSession->GetNumDropItems(&numItems);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (numItems < 1) return NS_ERROR_FAILURE;  // nothing to drop?
 
   // Combine any deletion and drop insertion into one transaction
@@ -192,21 +192,21 @@ NS_IMETHODIMP nsPlaintextEditor::InsertFromDrop(nsIDOMEvent* aDropEvent)
 
   nsCOMPtr<nsIDOMNode> newSelectionParent;
   rv = nsuiEvent->GetRangeParent(getter_AddRefs(newSelectionParent));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!newSelectionParent) return NS_ERROR_FAILURE;
 
   PRInt32 newSelectionOffset;
   rv = nsuiEvent->GetRangeOffset(&newSelectionOffset);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsISelection> selection;
   rv = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!selection) return NS_ERROR_FAILURE;
 
   PRBool isCollapsed;
   rv = selection->GetIsCollapsed(&isCollapsed);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // Check if mouse is in the selection
   // if so, jump through some hoops to determine if mouse is over selection (bail)
@@ -218,7 +218,7 @@ NS_IMETHODIMP nsPlaintextEditor::InsertFromDrop(nsIDOMEvent* aDropEvent)
 
     PRInt32 rangeCount;
     rv = selection->GetRangeCount(&rangeCount);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
 
     for (PRInt32 j = 0; j < rangeCount; j++)
     {
@@ -237,7 +237,7 @@ NS_IMETHODIMP nsPlaintextEditor::InsertFromDrop(nsIDOMEvent* aDropEvent)
     // Current doc is destination (set earlier)
     nsCOMPtr<nsIDOMDocument> srcdomdoc;
     rv = dragSession->GetSourceDocument(getter_AddRefs(srcdomdoc));
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
 
     if (cursorIsInSelection)
     {
@@ -289,7 +289,7 @@ NS_IMETHODIMP nsPlaintextEditor::InsertFromDrop(nsIDOMEvent* aDropEvent)
   for (i = 0; i < numItems; ++i)
   {
     rv = dragSession->GetData(trans, i);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
     if (!trans) return NS_OK; // NS_ERROR_FAILURE; Should we fail?
 
     // Beware! This may flush notifications via synchronous
@@ -320,11 +320,11 @@ NS_IMETHODIMP nsPlaintextEditor::CanDrag(nsIDOMEvent *aDragEvent, PRBool *aCanDr
    
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
     
   PRBool isCollapsed;
   res = selection->GetIsCollapsed(&isCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   // if we are collapsed, we have no selection so nothing to drag
   if ( isCollapsed )
@@ -335,7 +335,7 @@ NS_IMETHODIMP nsPlaintextEditor::CanDrag(nsIDOMEvent *aDragEvent, PRBool *aCanDr
   nsCOMPtr<nsIDOMNSEvent> nsevent(do_QueryInterface(aDragEvent));
   if (nsevent) {
     res = nsevent->GetTmpRealOriginalTarget(getter_AddRefs(eventTarget));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   if (eventTarget)
@@ -345,7 +345,7 @@ NS_IMETHODIMP nsPlaintextEditor::CanDrag(nsIDOMEvent *aDragEvent, PRBool *aCanDr
     {
       PRBool isTargetedCorrectly = PR_FALSE;
       res = selection->ContainsNode(eventTargetDomNode, PR_FALSE, &isTargetedCorrectly);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
 
       *aCanDrag = isTargetedCorrectly;
     }
@@ -360,13 +360,13 @@ NS_IMETHODIMP nsPlaintextEditor::DoDrag(nsIDOMEvent *aDragEvent)
 
   nsCOMPtr<nsITransferable> trans;
   rv = PutDragDataInTransferable(getter_AddRefs(trans));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!trans) return NS_OK; // maybe there was nothing to copy?
 
  /* get the drag service */
   nsCOMPtr<nsIDragService> dragService = 
            do_GetService("@mozilla.org/widget/dragservice;1", &rv);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   /* create an array of transferables */
   nsCOMPtr<nsISupportsArray> transferableArray;
@@ -376,7 +376,7 @@ NS_IMETHODIMP nsPlaintextEditor::DoDrag(nsIDOMEvent *aDragEvent)
 
   /* add the transferable to the array */
   rv = transferableArray->AppendElement(trans);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // check our transferable hooks (if any)
   nsCOMPtr<nsIDOMDocument> domdoc;
@@ -385,13 +385,13 @@ NS_IMETHODIMP nsPlaintextEditor::DoDrag(nsIDOMEvent *aDragEvent)
   /* invoke drag */
   nsCOMPtr<nsIDOMEventTarget> eventTarget;
   rv = aDragEvent->GetTarget(getter_AddRefs(eventTarget));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   nsCOMPtr<nsIDOMNode> domnode = do_QueryInterface(eventTarget);
 
   nsCOMPtr<nsIScriptableRegion> selRegion;
   nsCOMPtr<nsISelection> selection;
   rv = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   unsigned int flags;
   // in some cases we'll want to cut rather than copy... hmmmmm...
@@ -400,7 +400,7 @@ NS_IMETHODIMP nsPlaintextEditor::DoDrag(nsIDOMEvent *aDragEvent)
   nsCOMPtr<nsIDOMDragEvent> dragEvent(do_QueryInterface(aDragEvent));
   rv = dragService->InvokeDragSessionWithSelection(selection, transferableArray,
                                                    flags, dragEvent, nsnull);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   aDragEvent->StopPropagation();
   aDragEvent->PreventDefault();
@@ -472,7 +472,7 @@ NS_IMETHODIMP nsPlaintextEditor::CanPaste(PRInt32 aSelectionType, PRBool *aCanPa
 
   nsresult rv;
   nsCOMPtr<nsIClipboard> clipboard(do_GetService("@mozilla.org/widget/clipboard;1", &rv));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   // the flavors that we can deal with
   const char* textEditorFlavors[] = { kUnicodeMime };
@@ -481,7 +481,7 @@ NS_IMETHODIMP nsPlaintextEditor::CanPaste(PRInt32 aSelectionType, PRBool *aCanPa
   rv = clipboard->HasDataMatchingFlavors(textEditorFlavors,
                                          NS_ARRAY_LENGTH(textEditorFlavors),
                                          aSelectionType, &haveFlavors);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   
   *aCanPaste = haveFlavors;
   return NS_OK;
@@ -523,7 +523,7 @@ nsPlaintextEditor::SetupDocEncoder(nsIDocumentEncoder **aDocEncoder)
 {
   nsCOMPtr<nsIDOMDocument> domDoc;
   nsresult rv = GetDocument(getter_AddRefs(domDoc));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // find out if we're a plaintext control or not
   // get correct mimeType and document encoder flags set
@@ -543,15 +543,15 @@ nsPlaintextEditor::SetupDocEncoder(nsIDocumentEncoder **aDocEncoder)
     return NS_ERROR_OUT_OF_MEMORY;
 
   rv = encoder->Init(domDoc, mimeType, docEncoderFlags);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
     
   /* get the selection to be dragged */
   nsCOMPtr<nsISelection> selection;
   rv = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   rv = encoder->SetSelection(selection);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   *aDocEncoder = encoder;
   NS_ADDREF(*aDocEncoder);
@@ -564,12 +564,12 @@ nsPlaintextEditor::PutDragDataInTransferable(nsITransferable **aTransferable)
   *aTransferable = nsnull;
   nsCOMPtr<nsIDocumentEncoder> docEncoder;
   nsresult rv = SetupDocEncoder(getter_AddRefs(docEncoder));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // grab a string
   nsAutoString buffer;
   rv = docEncoder->EncodeToString(buffer);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // if we have an empty string, we're done; otherwise continue
   if (buffer.IsEmpty())
@@ -580,7 +580,7 @@ nsPlaintextEditor::PutDragDataInTransferable(nsITransferable **aTransferable)
   NS_ENSURE_SUCCESS(rv, rv);
 
   rv = dataWrapper->SetData(buffer);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   /* create html flavor transferable */
   nsCOMPtr<nsITransferable> trans = do_CreateInstance("@mozilla.org/widget/transferable;1", &rv);
@@ -591,18 +591,18 @@ nsPlaintextEditor::PutDragDataInTransferable(nsITransferable **aTransferable)
   {
     // Add the unicode flavor to the transferable
     rv = trans->AddDataFlavor(kUnicodeMime);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
   else
   {
     rv = trans->AddDataFlavor(kHTMLMime);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
 
     nsCOMPtr<nsIFormatConverter> htmlConverter = do_CreateInstance("@mozilla.org/widget/htmlformatconverter;1");
     NS_ENSURE_TRUE(htmlConverter, NS_ERROR_FAILURE);
 
     rv = trans->SetConverter(htmlConverter);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
 
   // QI the data object an |nsISupports| so that when the transferable holds
@@ -610,7 +610,7 @@ nsPlaintextEditor::PutDragDataInTransferable(nsITransferable **aTransferable)
   nsCOMPtr<nsISupports> nsisupportsDataWrapper = do_QueryInterface(dataWrapper);
   rv = trans->SetTransferData(IsPlaintextEditor() ? kUnicodeMime : kHTMLMime,
                    nsisupportsDataWrapper, buffer.Length() * sizeof(PRUnichar));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   *aTransferable = trans;
   NS_ADDREF(*aTransferable);
diff --git a/editor/libeditor/text/nsPlaintextEditor.cpp b/editor/libeditor/text/nsPlaintextEditor.cpp
index 74769c61046..6b7a254e836 100644
--- a/editor/libeditor/text/nsPlaintextEditor.cpp
+++ b/editor/libeditor/text/nsPlaintextEditor.cpp
@@ -167,7 +167,7 @@ NS_IMETHODIMP nsPlaintextEditor::Init(nsIDOMDocument *aDoc,
   // and "caret behaviour in selection" prefs
   GetDefaultEditorPrefs(mNewlineHandling, mCaretStyle);
 
-  if (NS_FAILED(rulesRes)) return rulesRes;
+  NS_ENSURE_SUCCESS(rulesRes, rulesRes);
   return res;
 }
 
@@ -331,7 +331,7 @@ NS_IMETHODIMP nsPlaintextEditor::InitRules()
 {
   // instantiate the rules for this text editor
   nsresult res = NS_NewTextEditRules(getter_AddRefs(mRules));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!mRules) return NS_ERROR_UNEXPECTED;
   return mRules->Init(this);
 }
@@ -483,20 +483,20 @@ NS_IMETHODIMP nsPlaintextEditor::CreateBRImpl(nsCOMPtr<nsIDOMNode> *aInOutParent
     {
       // split the text node
       res = SplitNode(node, theOffset, getter_AddRefs(tmp));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       res = GetNodeLocation(node, address_of(tmp), &offset);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
     // create br
     res = CreateNode(brType, tmp, offset, getter_AddRefs(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     *aInOutParent = tmp;
     *aInOutOffset = offset+1;
   }
   else
   {
     res = CreateNode(brType, node, theOffset, getter_AddRefs(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     (*aInOutOffset)++;
   }
 
@@ -506,11 +506,11 @@ NS_IMETHODIMP nsPlaintextEditor::CreateBRImpl(nsCOMPtr<nsIDOMNode> *aInOutParent
     nsCOMPtr<nsIDOMNode> parent;
     PRInt32 offset;
     res = GetNodeLocation(*outBRNode, address_of(parent), &offset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     nsCOMPtr<nsISelection> selection;
     res = GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));
     if (aSelect == eNext)
     {
@@ -546,26 +546,26 @@ NS_IMETHODIMP nsPlaintextEditor::InsertBR(nsCOMPtr<nsIDOMNode> *outBRNode)
 
   nsCOMPtr<nsISelection> selection;
   nsresult res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   PRBool bCollapsed;
   res = selection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!bCollapsed)
   {
     res = DeleteSelection(nsIEditor::eNone);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   nsCOMPtr<nsIDOMNode> selNode;
   PRInt32 selOffset;
   res = GetStartNodeAndOffset(selection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   res = CreateBR(selNode, selOffset, outBRNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
     
   // position selection after br
   res = GetNodeLocation(*outBRNode, address_of(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   nsCOMPtr<nsISelectionPrivate> selPriv(do_QueryInterface(selection));
   selPriv->SetInterlinePosition(PR_TRUE);
   return selection->Collapse(selNode, selOffset+1);
@@ -661,7 +661,7 @@ nsPlaintextEditor::ExtendSelectionForDelete(nsISelection *aSelection,
 
   PRBool bCollapsed;
   result = aSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   if (*aAction == eNextWord || *aAction == ePreviousWord
       || (*aAction == eNext && bCollapsed)
@@ -748,7 +748,7 @@ NS_IMETHODIMP nsPlaintextEditor::DeleteSelection(nsIEditor::EDirection aAction)
   // pre-process
   nsCOMPtr<nsISelection> selection;
   result = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   // If there is an existing selection when an extended delete is requested,
@@ -758,7 +758,7 @@ NS_IMETHODIMP nsPlaintextEditor::DeleteSelection(nsIEditor::EDirection aAction)
   //  existing selection without extending it.
   PRBool bCollapsed;
   result  = selection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!bCollapsed &&
       (aAction == eNextWord || aAction == ePreviousWord ||
        aAction == eToBeginningOfLine || aAction == eToEndOfLine))
@@ -766,7 +766,7 @@ NS_IMETHODIMP nsPlaintextEditor::DeleteSelection(nsIEditor::EDirection aAction)
     if (mCaretStyle == 1)
     {
       result = selection->CollapseToStart();
-      if (NS_FAILED(result)) return result;
+      NS_ENSURE_SUCCESS(result, result);
     }
     else
     { 
@@ -778,7 +778,7 @@ NS_IMETHODIMP nsPlaintextEditor::DeleteSelection(nsIEditor::EDirection aAction)
   ruleInfo.collapsedAction = aAction;
   PRBool cancel, handled;
   result = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!cancel && !handled)
   {
     result = DeleteSelectionImpl(aAction);
@@ -812,7 +812,7 @@ NS_IMETHODIMP nsPlaintextEditor::InsertText(const nsAString &aStringToInsert)
   // pre-process
   nsCOMPtr<nsISelection> selection;
   nsresult result = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!selection) return NS_ERROR_NULL_POINTER;
   nsAutoString resultString;
   // XXX can we trust instring to outlive ruleInfo,
@@ -825,7 +825,7 @@ NS_IMETHODIMP nsPlaintextEditor::InsertText(const nsAString &aStringToInsert)
 
   PRBool cancel, handled;
   result = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
   if (!cancel && !handled)
   {
     // we rely on rules code for now - no default implementation
@@ -852,20 +852,20 @@ NS_IMETHODIMP nsPlaintextEditor::InsertLineBreak()
   nsCOMPtr<nsISelection> selection;
   nsresult res;
   res = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   // Batching the selection and moving nodes out from under the caret causes
   // caret turds. Ask the shell to invalidate the caret now to avoid the turds.
   nsCOMPtr<nsIPresShell> shell;
   res = GetPresShell(getter_AddRefs(shell));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   shell->MaybeInvalidateCaretPosition();
 
   nsTextRulesInfo ruleInfo(nsTextEditRules::kInsertBreak);
   PRBool cancel, handled;
   res = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!cancel && !handled)
   {
     // create the new BR node
@@ -1073,7 +1073,7 @@ nsPlaintextEditor::SetWrapWidth(PRInt32 aWrapColumn)
   NS_NAMED_LITERAL_STRING(styleName, "style");
   nsAutoString styleValue;
   nsresult res = rootElement->GetAttribute(styleName, styleValue);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // We'll replace styles for these values:
   CutStyle("white-space", styleValue);
@@ -1282,7 +1282,7 @@ nsPlaintextEditor::GetAndInitDocEncoder(const nsAString& aFormatType,
 {
   nsCOMPtr<nsIPresShell> presShell;
   nsresult rv = GetPresShell(getter_AddRefs(presShell));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!presShell) return NS_ERROR_FAILURE;
 
   nsCAutoString formatType(NS_DOC_ENCODER_CONTRACTID_BASE);
@@ -1385,7 +1385,7 @@ nsPlaintextEditor::OutputToStream(nsIOutputStream* aOutputStream,
   {
     PRBool docEmpty;
     rv = GetDocumentIsEmpty(&docEmpty);
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
     
     if (docEmpty)
        return NS_OK;    // output nothing
@@ -1420,7 +1420,7 @@ nsPlaintextEditor::PasteAsQuotation(PRInt32 aSelectionType)
   // Get Clipboard Service
   nsresult rv;
   nsCOMPtr<nsIClipboard> clipboard(do_GetService("@mozilla.org/widget/clipboard;1", &rv));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   // Create generic Transferable for getting the data
   nsCOMPtr<nsITransferable> trans = do_CreateInstance("@mozilla.org/widget/transferable;1", &rv);
@@ -1491,7 +1491,7 @@ nsPlaintextEditor::InsertAsQuotation(const nsAString& aQuotedText,
   // get selection
   nsCOMPtr<nsISelection> selection;
   rv = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!selection) return NS_ERROR_NULL_POINTER;
 
   nsAutoEditBatch beginBatching(this);
@@ -1501,7 +1501,7 @@ nsPlaintextEditor::InsertAsQuotation(const nsAString& aQuotedText,
   nsTextRulesInfo ruleInfo(nsTextEditRules::kInsertElement);
   PRBool cancel, handled;
   rv = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (cancel) return NS_OK; // rules canceled the operation
   if (!handled)
   {
@@ -1575,17 +1575,17 @@ nsPlaintextEditor::Rewrap(PRBool aRespectNewlines)
   rv = SharedOutputString(nsIDocumentEncoder::OutputFormatted
                           | nsIDocumentEncoder::OutputLFLineBreak,
                           &isCollapsed, current);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsICiter> citer = new nsInternetCiter();
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
   if (!citer) return NS_ERROR_UNEXPECTED;
 
   nsString wrapped;
   PRUint32 firstLineOffset = 0;   // XXX need to reset this if there is a selection
   rv = citer->Rewrap(current, wrapCol, firstLineOffset, aRespectNewlines,
                      wrapped);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   if (isCollapsed)    // rewrap the whole document
     SelectAll();
@@ -1604,19 +1604,19 @@ nsPlaintextEditor::StripCites()
   PRBool isCollapsed;
   nsresult rv = SharedOutputString(nsIDocumentEncoder::OutputFormatted,
                                    &isCollapsed, current);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsICiter> citer = new nsInternetCiter();
   if (!citer) return NS_ERROR_UNEXPECTED;
 
   nsString stripped;
   rv = citer->StripCites(current, stripped);
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);
 
   if (isCollapsed)    // rewrap the whole document
   {
     rv = SelectAll();
-    if (NS_FAILED(rv)) return rv;
+    NS_ENSURE_SUCCESS(rv, rv);
   }
 
   return InsertText(stripped);
@@ -1652,7 +1652,7 @@ nsPlaintextEditor::SetCompositionString(const nsAString& aCompositionString,
 
   nsCOMPtr<nsISelection> selection;
   nsresult result = GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(result)) return result;
+  NS_ENSURE_SUCCESS(result, result);
 
   nsRefPtr<nsCaret> caretP = ps->GetCaret();
 
diff --git a/editor/libeditor/text/nsTextEditRules.cpp b/editor/libeditor/text/nsTextEditRules.cpp
index 4f878865094..4d0f2b86617 100644
--- a/editor/libeditor/text/nsTextEditRules.cpp
+++ b/editor/libeditor/text/nsTextEditRules.cpp
@@ -151,7 +151,7 @@ nsTextEditRules::Init(nsPlaintextEditor *aEditor)
   // Put in a magic br if needed. This method handles null selection,
   // which should never happen anyway
   nsresult res = CreateBogusNodeIfNeeded(selection);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // If the selection hasn't been set up yet, set it up collapsed to the end of
   // our editable content.
@@ -167,7 +167,7 @@ nsTextEditRules::Init(nsPlaintextEditor *aEditor)
   {
     // ensure trailing br node
     res = CreateTrailingBRIfNeeded();
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   if (body)
@@ -179,15 +179,15 @@ nsTextEditRules::Init(nsPlaintextEditor *aEditor)
     wholeDoc->SetStart(body,0);
     nsCOMPtr<nsIDOMNodeList> list;
     res = body->GetChildNodes(getter_AddRefs(list));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!list) return NS_ERROR_FAILURE;
 
     PRUint32 listCount;
     res = list->GetLength(&listCount);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     res = wholeDoc->SetEnd(body, listCount);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // replace newlines in that range with breaks
     res = ReplaceNewlines(wholeDoc);
@@ -254,7 +254,7 @@ nsTextEditRules::AfterEdit(PRInt32 action, nsIEditor::EDirection aDirection)
   {
     nsCOMPtr<nsISelection>selection;
     res = mEditor->GetSelection(getter_AddRefs(selection));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   
     res = mEditor->HandleInlineSpellCheck(action, selection,
                                           mCachedSelectionNode, mCachedSelectionOffset,
@@ -443,15 +443,15 @@ nsTextEditRules::WillInsertBreak(nsISelection *aSelection, PRBool *aCancel, PRBo
     // if the selection isn't collapsed, delete it.
     PRBool bCollapsed;
     nsresult res = aSelection->GetIsCollapsed(&bCollapsed);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!bCollapsed)
     {
       res = mEditor->DeleteSelection(nsIEditor::eNone);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
 
     res = WillInsert(aSelection, aCancel);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     // initialize out param
     // we want to ignore result of WillInsert()
     *aCancel = PR_FALSE;
@@ -477,7 +477,7 @@ nsTextEditRules::DidInsertBreak(nsISelection *aSelection, nsresult aResult)
   nsCOMPtr<nsIDOMNode> selNode;
   nsresult res;
   res = mEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // confirm we are at end of document
   if (selOffset == 0) return NS_OK;  // can't be after a br if we are at offset 0
   nsIDOMElement *rootElem = mEditor->GetRoot();
@@ -498,13 +498,13 @@ nsTextEditRules::DidInsertBreak(nsISelection *aSelection, nsresult aResult)
     // like table cells won't grow in height.
     nsCOMPtr<nsIDOMNode> brNode;
     res = CreateMozBR(selNode, selOffset, address_of(brNode));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     res = nsEditor::GetNodeLocation(brNode, address_of(selNode), &selOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     selPrivate->SetInterlinePosition(PR_TRUE);
     res = aSelection->Collapse(selNode, selOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return res;
 }
@@ -514,7 +514,7 @@ GetTextNode(nsISelection *selection, nsEditor *editor) {
   PRInt32 selOffset;
   nsCOMPtr<nsIDOMNode> selNode;
   nsresult res = editor->GetStartNodeAndOffset(selection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return nsnull;
+  NS_ENSURE_SUCCESS(res, nsnull);
   if (!editor->IsTextNode(selNode)) {
     // Get an nsINode from the nsIDOMNode
     nsCOMPtr<nsINode> node = do_QueryInterface(selNode);
@@ -641,7 +641,7 @@ nsTextEditRules::WillInsertText(PRInt32          aAction,
   // handle docs with a max length
   // NOTE, this function copies inString into outString for us.
   nsresult res = TruncateInsertionIfNeeded(aSelection, inString, outString, aMaxLength);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   PRUint32 start = 0;
   PRUint32 end = 0;  
@@ -651,21 +651,21 @@ nsTextEditRules::WillInsertText(PRInt32          aAction,
   {
     res = mEditor->GetTextSelectionOffsets(aSelection, start, end);
     NS_ASSERTION((NS_SUCCEEDED(res)), "getTextSelectionOffsets failed!");
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   // if the selection isn't collapsed, delete it.
   PRBool bCollapsed;
   res = aSelection->GetIsCollapsed(&bCollapsed);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!bCollapsed)
   {
     res = mEditor->DeleteSelection(nsIEditor::eNone);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
 
   res = WillInsert(aSelection, aCancel);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   // initialize out param
   // we want to ignore result of WillInsert()
   *aCancel = PR_FALSE;
@@ -677,7 +677,7 @@ nsTextEditRules::WillInsertText(PRInt32          aAction,
   {
     if (aAction == kInsertTextIME)  {
       res = RemoveIMETextFromPWBuf(start, outString);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
 
@@ -717,14 +717,14 @@ nsTextEditRules::WillInsertText(PRInt32          aAction,
       else
       {
         mTimer = do_CreateInstance("@mozilla.org/timer;1", &res);
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
       mTimer->InitWithCallback(this, 600, nsITimer::TYPE_ONE_SHOT);
     } 
     else 
     {
       res = FillBufWithPWChars(outString, outString->Length());
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
 
@@ -732,7 +732,7 @@ nsTextEditRules::WillInsertText(PRInt32          aAction,
   nsCOMPtr<nsIDOMNode> selNode;
   PRInt32 selOffset;
   res = mEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(selNode), &selOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // don't put text in places that can't have it
   if (!mEditor->IsTextNode(selNode) && !mEditor->CanContainTag(selNode, NS_LITERAL_STRING("#text")))
@@ -741,13 +741,13 @@ nsTextEditRules::WillInsertText(PRInt32          aAction,
   // we need to get the doc
   nsCOMPtr<nsIDOMDocument>doc;
   res = mEditor->GetDocument(getter_AddRefs(doc));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!doc) return NS_ERROR_NULL_POINTER;
     
   if (aAction == kInsertTextIME) 
   { 
     res = mEditor->InsertTextImpl(*outString, address_of(selNode), &selOffset, doc);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   else // aAction == kInsertText
   {
@@ -759,7 +759,7 @@ nsTextEditRules::WillInsertText(PRInt32          aAction,
     // We remember this so that we know how to handle tabs.
     PRBool isPRE;
     res = mEditor->IsPreformatted(selNode, &isPRE);
-    if (NS_FAILED(res)) return res;    
+    NS_ENSURE_SUCCESS(res, res);    
 
     // don't spaz my selection in subtransactions
     nsAutoTxnsConserveSelection dontSpazMySelection(mEditor);
@@ -835,7 +835,7 @@ nsTextEditRules::WillInsertText(PRInt32          aAction,
         {
           res = mEditor->InsertTextImpl(subStr, address_of(curNode), &curOffset, doc);
         }
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     else
@@ -878,7 +878,7 @@ nsTextEditRules::WillInsertText(PRInt32          aAction,
         {
           res = mEditor->InsertTextImpl(subStr, address_of(curNode), &curOffset, doc);
         }
-        if (NS_FAILED(res)) return res;
+        NS_ENSURE_SUCCESS(res, res);
       }
     }
     outString->Assign(tString);
@@ -1006,18 +1006,18 @@ nsTextEditRules::WillDeleteSelection(nsISelection *aSelection,
     nsCOMPtr<nsIDOMNode> startNode;
     PRInt32 startOffset;
     res = mEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(startNode), &startOffset);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (!startNode) return NS_ERROR_FAILURE;
     
     PRBool bCollapsed;
     res = aSelection->GetIsCollapsed(&bCollapsed);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   
     if (!bCollapsed) return NS_OK;
 
     // Test for distance between caret and text that will be deleted
     res = CheckBidiLevelForDeletion(aSelection, startNode, startOffset, aCollapsedAction, aCancel);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     if (*aCancel) return NS_OK;
 
     res = mEditor->ExtendSelectionForDelete(aSelection, &aCollapsedAction);
@@ -1040,7 +1040,7 @@ nsTextEditRules::DidDeleteSelection(nsISelection *aSelection,
   nsCOMPtr<nsIDOMNode> startNode;
   PRInt32 startOffset;
   nsresult res = mEditor->GetStartNodeAndOffset(aSelection, getter_AddRefs(startNode), &startOffset);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   if (!startNode) return NS_ERROR_FAILURE;
   
   // delete empty text nodes at selection
@@ -1049,13 +1049,13 @@ nsTextEditRules::DidDeleteSelection(nsISelection *aSelection,
     nsCOMPtr<nsIDOMText> textNode = do_QueryInterface(startNode);
     PRUint32 strLength;
     res = textNode->GetLength(&strLength);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     
     // are we in an empty text node?
     if (!strLength)
     {
       res = mEditor->DeleteNode(startNode);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     }
   }
   if (!mDidExplicitlySetInterline)
@@ -1135,7 +1135,7 @@ nsTextEditRules::DidRedo(nsISelection *aSelection, nsresult aResult)
       nsCOMPtr<nsIDOMNodeList> nodeList;
       res = theRoot->GetElementsByTagName(NS_LITERAL_STRING("br"),
                                           getter_AddRefs(nodeList));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (nodeList)
       {
         PRUint32 len;
@@ -1204,10 +1204,10 @@ nsTextEditRules::ReplaceNewlines(nsIDOMRange *aRange)
   nsresult res;
   nsCOMPtr<nsIContentIterator> iter =
        do_CreateInstance("@mozilla.org/content/post-content-iterator;1", &res);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   res = iter->Init(aRange);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   
   nsCOMArray<nsIDOMCharacterData> arrayOfNodes;
   
@@ -1222,7 +1222,7 @@ nsTextEditRules::ReplaceNewlines(nsIDOMRange *aRange)
     {
       PRBool isPRE;
       res = mEditor->IsPreformatted(node, &isPRE);
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
       if (isPRE)
       {
         nsCOMPtr<nsIDOMCharacterData> data = do_QueryInterface(node);
@@ -1257,14 +1257,14 @@ nsTextEditRules::ReplaceNewlines(nsIDOMRange *aRange)
       //         or, failing that, undo is disabled
       res = mEditor->CreateTxnForDeleteText(textNode, offset, 1,
                                             getter_AddRefs(txn));
-      if (NS_FAILED(res))  return res; 
+      NS_ENSURE_SUCCESS(res, res); 
       if (!txn)  return NS_ERROR_OUT_OF_MEMORY;
       res = mEditor->DoTransaction(txn); 
-      if (NS_FAILED(res))  return res; 
+      NS_ENSURE_SUCCESS(res, res); 
       
       // insert a break
       res = mEditor->CreateBR(textNode, offset, address_of(brNode));
-      if (NS_FAILED(res)) return res;
+      NS_ENSURE_SUCCESS(res, res);
     } while (1);  // break used to exit while loop
   }
   return res;
@@ -1282,7 +1282,7 @@ nsTextEditRules::CreateTrailingBRIfNeeded()
   nsCOMPtr<nsIDOMNode> lastChild;
   nsresult res = body->GetLastChild(getter_AddRefs(lastChild));
   // assuming CreateBogusNodeIfNeeded() has been called first
-  if (NS_FAILED(res)) return res;  
+  NS_ENSURE_SUCCESS(res, res);  
   if (!lastChild) return NS_ERROR_NULL_POINTER;
 
   if (!nsTextEditUtils::IsBreak(lastChild))
@@ -1290,7 +1290,7 @@ nsTextEditRules::CreateTrailingBRIfNeeded()
     nsAutoTxnsConserveSelection dontSpazMySelection(mEditor);
     PRUint32 rootLen;
     res = mEditor->GetLengthOfDOMNode(body, rootLen);
-    if (NS_FAILED(res)) return res; 
+    NS_ENSURE_SUCCESS(res, res); 
     nsCOMPtr<nsIDOMNode> unused;
     res = CreateMozBR(body, rootLen, address_of(unused));
   }
@@ -1340,7 +1340,7 @@ nsTextEditRules::CreateBogusNodeIfNeeded(nsISelection *aSelection)
     // create a br
     nsCOMPtr<nsIContent> newContent;
     res = mEditor->CreateHTMLContent(NS_LITERAL_STRING("br"), getter_AddRefs(newContent));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
     nsCOMPtr<nsIDOMElement>brElement = do_QueryInterface(newContent);
 
     // set mBogusNode to be the newly created <br>
@@ -1353,7 +1353,7 @@ nsTextEditRules::CreateBogusNodeIfNeeded(nsISelection *aSelection)
     
     // put the node in the document
     res = mEditor->InsertNode(mBogusNode, body, 0);
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
 
     // set selection
     aSelection->Collapse(body, 0);
@@ -1464,9 +1464,9 @@ nsresult nsTextEditRules::HideLastPWInput() {
   nsCOMPtr<nsISelection> selection;
   PRUint32 start, end;
   nsresult res = mEditor->GetSelection(getter_AddRefs(selection));
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
   res = mEditor->GetTextSelectionOffsets(selection, start, end);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   nsCOMPtr<nsIDOMNode> selNode = GetTextNode(selection, mEditor);
   if (!selNode)
@@ -1515,14 +1515,14 @@ nsTextEditRules::CreateMozBR(nsIDOMNode *inParent, PRInt32 inOffset, nsCOMPtr<ns
   if (!inParent || !outBRNode) return NS_ERROR_NULL_POINTER;
 
   nsresult res = mEditor->CreateBR(inParent, inOffset, outBRNode);
-  if (NS_FAILED(res)) return res;
+  NS_ENSURE_SUCCESS(res, res);
 
   // give it special moz attr
   nsCOMPtr<nsIDOMElement> brElem = do_QueryInterface(*outBRNode);
   if (brElem)
   {
     res = mEditor->SetAttribute(brElem, NS_LITERAL_STRING("type"), NS_LITERAL_STRING("_moz"));
-    if (NS_FAILED(res)) return res;
+    NS_ENSURE_SUCCESS(res, res);
   }
   return res;
 }
diff --git a/editor/txtsvc/src/nsFilteredContentIterator.cpp b/editor/txtsvc/src/nsFilteredContentIterator.cpp
index e2406376615..d81090d938e 100644
--- a/editor/txtsvc/src/nsFilteredContentIterator.cpp
+++ b/editor/txtsvc/src/nsFilteredContentIterator.cpp
@@ -271,10 +271,10 @@ ContentIsInTraversalRange(nsIContent *aContent,   PRBool aIsPreMode,
   PRInt32 startRes;
   PRInt32 endRes;
   nsresult rv = nsTextServicesDocument::ComparePoints(aStartNode, aStartOffset, parentNode, indx, &startRes);
-  if (NS_FAILED(rv)) return PR_FALSE;
+  NS_ENSURE_SUCCESS(rv, PR_FALSE);
 
   rv = nsTextServicesDocument::ComparePoints(aEndNode,   aEndOffset,   parentNode, indx,  &endRes);
-  if (NS_FAILED(rv)) return PR_FALSE;
+  NS_ENSURE_SUCCESS(rv, PR_FALSE);
 
   return (startRes <= 0) && (endRes >= 0);
 }