Merge 139024

Source/WebCore/page/scrolling/chromium/ScrollingCoordinatorChromium.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 93 matching lines @@
 ScrollingCoordinatorChromium::~ScrollingCoordinatorChromium()
 {
     delete m_private;
 }
 
 void ScrollingCoordinatorChromium::frameViewLayoutUpdated(FrameView*)
 {
     ASSERT(m_page);
 
     // Compute the region of the page that we can't do fast scrolling for. This currently includes
-    // all scrollable areas, such as subframes, overflow divs and list boxes. We need to do this even if the
-    // frame view whose layout was updated is not the main frame.
+    // all scrollable areas, such as subframes, overflow divs and list boxes, whose composited
+    // scrolling are not enabled. We need to do this even if the frame view whose layout was updated
+    // is not the main frame.
     Region nonFastScrollableRegion = computeNonFastScrollableRegion(m_page->mainFrame(), IntPoint());
     setNonFastScrollableRegion(nonFastScrollableRegion);
 #if ENABLE(TOUCH_EVENT_TRACKING)
     Vector<IntRect> touchEventTargetRects;
     computeAbsoluteTouchEventTargetRects(m_page->mainFrame()->document(), touchEventTargetRects);
     setTouchEventTargetRects(touchEventTargetRects);
 #endif
 }
 
 void ScrollingCoordinatorChromium::touchEventTargetRectsDidChange(const Document* document)
@@ skipping 161 matching lines @@
     }
 }
 
 void ScrollingCoordinatorChromium::recomputeWheelEventHandlerCountForFrameView(FrameView* frameView)
 {
     UNUSED_PARAM(frameView);
     setWheelEventHandlerCount(computeCurrentWheelEventHandlerCount());
 }
 
 }