Fire overflowchanged events at raf timing

Source/core/rendering/RenderBlock.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 110 matching lines @@
 
         bool hasHorizontalLayoutOverflow = m_block->hasHorizontalLayoutOverflow();
         bool hasVerticalLayoutOverflow = m_block->hasVerticalLayoutOverflow();
 
         bool horizontalLayoutOverflowChanged = hasHorizontalLayoutOverflow != m_hadHorizontalLayoutOverflow;
         bool verticalLayoutOverflowChanged = hasVerticalLayoutOverflow != m_hadVerticalLayoutOverflow;
 
         if (!horizontalLayoutOverflowChanged && !verticalLayoutOverflowChanged)
             return;
 
-        if (FrameView* frameView = m_block->frameView()) {
-            RefPtr<OverflowEvent> event = OverflowEvent::create(horizontalLayoutOverflowChanged, hasHorizontalLayoutOverflow, verticalLayoutOverflowChanged, hasVerticalLayoutOverflow);
-            event->setTarget(m_block->node());
-            frameView->scheduleOverflowEvent(event);
-        }
+        RefPtr<OverflowEvent> event = OverflowEvent::create(horizontalLayoutOverflowChanged, hasHorizontalLayoutOverflow, verticalLayoutOverflowChanged, hasVerticalLayoutOverflow);
+        event->setTarget(m_block->node());
+        m_block->document().enqueueAnimationFrameEvent(event.release());
     }
 
 private:
     const RenderBlock* m_block;
     bool m_shouldDispatchEvent;
     bool m_hadHorizontalLayoutOverflow;
     bool m_hadVerticalLayoutOverflow;
 };
 
 RenderBlock::RenderBlock(ContainerNode* node)
@@ skipping 5642 matching lines @@
 void RenderBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const RenderObject* obj) const
 {
     showRenderObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace WebCore