Subtree caching implementation in blink-core

Source/core/layout/LayoutPart.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Simon Hausmann <hausmann@kde.org>
  *           (C) 2000 Stefan Schimanski (1Stein@gmx.de)
  * Copyright (C) 2004, 2005, 2006, 2009 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. 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 320 matching lines @@
     RefPtrWillBeRawPtr<Node> protectedNode(node());
     widget->setFrameRect(newFrame);
     return widget->frameRect().size() != newFrame.size();
 }
 
 void LayoutPart::invalidatePaintOfSubtreesIfNeeded(PaintInvalidationState& paintInvalidationState)
 {
     if (widget() && widget()->isFrameView()) {
         FrameView* childFrameView = toFrameView(widget());
         PaintInvalidationState childViewPaintInvalidationState(*childFrameView->layoutView(), paintInvalidationState);
-        toFrameView(widget())->invalidateTreeIfNeeded(childViewPaintInvalidationState);
+        childFrameView->invalidateTreeIfNeeded(childViewPaintInvalidationState);
     }
 
     LayoutReplaced::invalidatePaintOfSubtreesIfNeeded(paintInvalidationState);
 }
 
+void LayoutPart::clearRepaintFlagsOfSubtrees()
+{
+    if (widget() && widget()->isFrameView())
+        toFrameView(widget())->layoutView()->clearRepaintFlagsRecursively();
 }
+
+}