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

@@ -305,6 +305,7 @@ 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;
 
     // Time to mess with our security context... See comments in GetValue()
@@ -339,6 +340,7 @@ nsTextControlFrame::EnsureEditorInitialized()
     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.
@@ -348,7 +350,8 @@ nsTextControlFrame::EnsureEditorInitialized()
     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;
 }