Bug 1083629 Use nsHTMLEditor::IsAcceptableInputEvent() instead of nsEditor::IsDescendantOfEditorRoot() for checking if a mouse down event target is in focused HTML editor r=ehsan

editor/libeditor/nsHTMLEditorEventListener.cpp

@@ -72,6 +72,11 @@ nsresult
 nsHTMLEditorEventListener::MouseDown(nsIDOMMouseEvent* aMouseEvent)
 {
   nsHTMLEditor* htmlEditor = GetHTMLEditor();
+  // Contenteditable should disregard mousedowns outside it.
+  // IsAcceptableInputEvent() checks it for a mouse event.
+  if (!htmlEditor->IsAcceptableInputEvent(aMouseEvent)) {
+    return NS_OK;
+  }
 
   // Detect only "context menu" click
   // XXX This should be easier to do!
@@ -93,11 +98,6 @@ nsHTMLEditorEventListener::MouseDown(nsIDOMMouseEvent* aMouseEvent)
   NS_ENSURE_TRUE(target, NS_ERROR_NULL_POINTER);
   nsCOMPtr<nsIDOMElement> element = do_QueryInterface(target);
 
-  // Contenteditable should disregard mousedowns outside it
-  if (element && !htmlEditor->IsDescendantOfEditorRoot(element)) {
-    return NS_OK;
-  }
-
   if (isContextClick || (buttonNumber == 0 && clickCount == 2)) {
     nsCOMPtr<nsISelection> selection;
     mEditor->GetSelection(getter_AddRefs(selection));