Bug 802985, PreDestroy editor, r=ehsan , a=lsblakk

--HG--
extra : rebase_source : 224d67b3a3c108cf1d1822d2e1cdd2d1757137a0

content/html/content/src/nsTextEditorState.cpp

@@ -1122,6 +1122,26 @@ nsTextEditorState::BindToFrame(nsTextControlFrame* aFrame)
   return NS_OK;
 }
 
+struct PreDestroyer
+{
+  void Init(nsIEditor* aEditor)
+  {
+    mNewEditor = aEditor;
+  }
+  ~PreDestroyer()
+  {
+    if (mNewEditor) {
+      mNewEditor->PreDestroy(true);
+    }
+  }
+  void Swap(nsCOMPtr<nsIEditor>& aEditor)
+  {
+    return mNewEditor.swap(aEditor);
+  }
+private:
+  nsCOMPtr<nsIEditor> mNewEditor;
+};
+
 nsresult
 nsTextEditorState::PrepareEditor(const nsAString *aValue)
 {
@@ -1168,12 +1188,14 @@ nsTextEditorState::PrepareEditor(const nsAString *aValue)
   bool shouldInitializeEditor = false;
   nsCOMPtr<nsIEditor> newEditor; // the editor that we might create
   nsresult rv = NS_OK;
+  PreDestroyer preDestroyer;
   if (!mEditor) {
     shouldInitializeEditor = true;
 
     // Create an editor
     newEditor = do_CreateInstance(kTextEditorCID, &rv);
     NS_ENSURE_SUCCESS(rv, rv);
+    preDestroyer.Init(newEditor);
 
     // Make sure we clear out the non-breaking space before we initialize the editor
     rv = mBoundFrame->UpdateValueDisplay(false, true);
@@ -1302,7 +1324,7 @@ nsTextEditorState::PrepareEditor(const nsAString *aValue)
 
   if (shouldInitializeEditor) {
     // Hold on to the newly created editor
-    mEditor = newEditor;
+    preDestroyer.Swap(mEditor);
   }
 
   // If we have a default value, insert it under the div we created

editor/libeditor/text/nsTextEditRules.cpp

@@ -104,7 +104,7 @@ nsTextEditRules::Init(nsPlaintextEditor *aEditor)
   mEditor = aEditor;  // we hold a non-refcounted reference back to our editor
   nsCOMPtr<nsISelection> selection;
   mEditor->GetSelection(getter_AddRefs(selection));
-  NS_ASSERTION(selection, "editor cannot get selection");
+  NS_WARN_IF_FALSE(selection, "editor cannot get selection");
 
   // Put in a magic br if needed. This method handles null selection,
   // which should never happen anyway

layout/forms/nsTextControlFrame.cpp

@@ -305,50 +305,53 @@ nsTextControlFrame::EnsureEditorInitialized()
 
   // Make sure that editor init doesn't do things that would kill us off
   // (especially off the script blockers it'll create for its DOM mutations).
-  nsAutoScriptBlocker scriptBlocker;
+  {
+    nsAutoScriptBlocker scriptBlocker;
 
-  // Time to mess with our security context... See comments in GetValue()
-  // for why this is needed.
-  nsCxPusher pusher;
-  pusher.PushNull();
+    // Time to mess with our security context... See comments in GetValue()
+    // for why this is needed.
+    nsCxPusher pusher;
+    pusher.PushNull();
 
-  // Make sure that we try to focus the content even if the method fails
-  class EnsureSetFocus {
-  public:
-    explicit EnsureSetFocus(nsTextControlFrame* aFrame)
-      : mFrame(aFrame) {}
-    ~EnsureSetFocus() {
-      if (nsContentUtils::IsFocusedContent(mFrame->GetContent()))
-        mFrame->SetFocus(true, false);
-    }
-  private:
-    nsTextControlFrame *mFrame;
-  };
-  EnsureSetFocus makeSureSetFocusHappens(this);
+    // Make sure that we try to focus the content even if the method fails
+    class EnsureSetFocus {
+    public:
+      explicit EnsureSetFocus(nsTextControlFrame* aFrame)
+        : mFrame(aFrame) {}
+      ~EnsureSetFocus() {
+        if (nsContentUtils::IsFocusedContent(mFrame->GetContent()))
+          mFrame->SetFocus(true, false);
+      }
+    private:
+      nsTextControlFrame *mFrame;
+    };
+    EnsureSetFocus makeSureSetFocusHappens(this);
 
 #ifdef DEBUG
-  // Make sure we are not being called again until we're finished.
-  // If reentrancy happens, just pretend that we don't have an editor.
-  const EditorInitializerEntryTracker tracker(*this);
-  NS_ASSERTION(!tracker.EnteredMoreThanOnce(),
-               "EnsureEditorInitialized has been called while a previous call was in progress");
+    // Make sure we are not being called again until we're finished.
+    // If reentrancy happens, just pretend that we don't have an editor.
+    const EditorInitializerEntryTracker tracker(*this);
+    NS_ASSERTION(!tracker.EnteredMoreThanOnce(),
+                 "EnsureEditorInitialized has been called while a previous call was in progress");
 #endif
 
-  // Create an editor for the frame, if one doesn't already exist
-  nsCOMPtr<nsITextControlElement> txtCtrl = do_QueryInterface(GetContent());
-  NS_ASSERTION(txtCtrl, "Content not a text control element");
-  nsresult rv = txtCtrl->CreateEditor();
-  NS_ENSURE_SUCCESS(rv, rv);
+    // Create an editor for the frame, if one doesn't already exist
+    nsCOMPtr<nsITextControlElement> txtCtrl = do_QueryInterface(GetContent());
+    NS_ASSERTION(txtCtrl, "Content not a text control element");
+    nsresult rv = txtCtrl->CreateEditor();
+    NS_ENSURE_SUCCESS(rv, rv);
+    NS_ENSURE_STATE(weakFrame.IsAlive());
 
-  // Turn on mUseEditor so that subsequent calls will use the
-  // editor.
-  mUseEditor = true;
+    // Turn on mUseEditor so that subsequent calls will use the
+    // editor.
+    mUseEditor = true;
 
-  // Set the selection to the beginning of the text field.
-  if (weakFrame.IsAlive()) {
-    SetSelectionEndPoints(0, 0);
+    // Set the selection to the beginning of the text field.
+    if (weakFrame.IsAlive()) {
+      SetSelectionEndPoints(0, 0);
+    }
   }
-
+  NS_ENSURE_STATE(weakFrame.IsAlive());
   return NS_OK;
 }
 
@@ -1098,8 +1101,10 @@ nsTextControlFrame::GetSelectionRange(int32_t* aSelectionStart,
     return NS_OK;
   }
 
-  nsContentUtils::GetSelectionInTextControl(typedSel,
-    GetRootNodeAndInitializeEditor(), *aSelectionStart, *aSelectionEnd);
+  mozilla::dom::Element* root = GetRootNodeAndInitializeEditor();
+  NS_ENSURE_STATE(root);
+  nsContentUtils::GetSelectionInTextControl(typedSel, root,
+                                            *aSelectionStart, *aSelectionEnd);
 
   return NS_OK;
 }