Bug 832611 - Use NotifyDestroyingFrame to remove frames from the OverflowChangedTracker. r=roc

layout/base/RestyleTracker.h

@@ -49,29 +49,12 @@ public:
   }
 
   /**
-   * Remove a frame and all descendants of that frame.
+   * Remove a frame.
    */
-  void RemoveFrameAndDescendants(nsIFrame* aFrame) {
+  void RemoveFrame(nsIFrame* aFrame) {
     if (mEntryList.contains(Entry(aFrame, 0, false))) {
       delete mEntryList.remove(Entry(aFrame, 0, false));
     }
-    if (mEntryList.empty()) {
-      return;
-    }
-
-    nsAutoTArray<nsIFrame::ChildList,4> childListArray;
-    aFrame->GetCrossDocChildLists(&childListArray);
-
-    nsIFrame::ChildListArrayIterator lists(childListArray);
-    for (; !lists.IsDone(); lists.Next()) {
-      nsFrameList::Enumerator childFrames(lists.CurrentList());
-      for (; !childFrames.AtEnd(); childFrames.Next()) {
-        RemoveFrameAndDescendants(childFrames.get());
-        if (mEntryList.empty()) {
-          return;
-        }
-      }
-    }
   }
 
   /**
@@ -138,26 +121,19 @@ private:
     }
  
     /**
-     * Sort by the depth in the frame tree, and then
-     * the frame pointer.
+     * Sort by the frame pointer.
      */
     bool operator<(const Entry& aOther) const
     {
-      if (mDepth != aOther.mDepth) {
-        // nsTPriorityQueue implements a min-heap and we
-        // want the highest depth first, so reverse this check.
-        return mDepth > aOther.mDepth;
-      }
-
       return mFrame < aOther.mFrame;
     }
 
     static int compare(const Entry& aOne, const Entry& aTwo)
     {
-      if (aOne < aTwo) {
-        return -1;
-      } else if (aOne == aTwo) {
+      if (aOne == aTwo) {
         return 0;
+      } else if (aOne < aTwo) {
+        return -1;
       } else {
         return 1;
       }

layout/base/nsCSSFrameConstructor.cpp

@@ -1430,6 +1430,7 @@ nsCSSFrameConstructor::nsCSSFrameConstructor(nsIDocument *aDocument,
   , mInStyleRefresh(false)
   , mHoverGeneration(0)
   , mRebuildAllExtraHint(nsChangeHint(0))
+  , mOverflowChangedTracker(nullptr)
   , mAnimationGeneration(0)
   , mPendingRestyles(ELEMENT_HAS_PENDING_RESTYLE |
                      ELEMENT_IS_POTENTIAL_RESTYLE_ROOT, this)
@@ -1509,6 +1510,10 @@ nsCSSFrameConstructor::NotifyDestroyingFrame(nsIFrame* aFrame)
     CountersDirty();
   }
 
+  if (mOverflowChangedTracker) {
+    mOverflowChangedTracker->RemoveFrame(aFrame);
+  }
+
   nsFrameManager::NotifyDestroyingFrame(aFrame);
 }
 
@@ -8118,6 +8123,10 @@ nsCSSFrameConstructor::ProcessRestyledFrames(nsStyleChangeList& aChangeList,
 
   SAMPLE_LABEL("CSS", "ProcessRestyledFrames");
 
+  MOZ_ASSERT(!GetOverflowChangedTracker(), 
+             "Can't have multiple overflow changed trackers!");
+  SetOverflowChangedTracker(&aTracker);
+
   // Make sure to not rebuild quote or counter lists while we're
   // processing restyles
   BeginUpdate();
@@ -8202,9 +8211,6 @@ nsCSSFrameConstructor::ProcessRestyledFrames(nsStyleChangeList& aChangeList,
       // the style resolution we will do for the frame construction
       // happens async when we're not in an animation restyle already,
       // problems could arise.
-      if (content->GetPrimaryFrame()) {
-        aTracker.RemoveFrameAndDescendants(content->GetPrimaryFrame());
-      }
       RecreateFramesForContent(content, false);
     } else {
       NS_ASSERTION(frame, "This shouldn't happen");
@@ -8306,6 +8312,7 @@ nsCSSFrameConstructor::ProcessRestyledFrames(nsStyleChangeList& aChangeList,
 #endif
   }
 
+  SetOverflowChangedTracker(nullptr);
   aChangeList.Clear();
   return NS_OK;
 }

layout/base/nsCSSFrameConstructor.h

@@ -307,6 +307,15 @@ public:
     PostRestyleEventCommon(aElement, aRestyleHint, aMinChangeHint, true);
   }
 
+  OverflowChangedTracker *GetOverflowChangedTracker() const 
+  { 
+    return mOverflowChangedTracker; 
+  }
+  void SetOverflowChangedTracker(OverflowChangedTracker *aTracker)
+  {
+    mOverflowChangedTracker = aTracker;    
+  }
+
 private:
   /**
    * Notify the frame constructor that an element needs to have its
@@ -1895,6 +1904,8 @@ private:
 
   nsCOMPtr<nsILayoutHistoryState> mTempFrameTreeState;
 
+  OverflowChangedTracker *mOverflowChangedTracker;
+
   // The total number of animation flushes by this frame constructor.
   // Used to keep the layer and animation manager in sync.
   uint64_t mAnimationGeneration;