Update PaintLayer size during layout, not after.

third_party/WebKit/Source/core/page/ChromeClient.h

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple, Inc. All rights
  * reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  * Copyright (C) 2012 Samsung Electronics. 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
  * version 2 of the License, or (at your option) any later version.
@@ skipping 187 matching lines @@
 
   virtual void DispatchViewportPropertiesDidChange(
       const ViewportDescription&) const {}
 
   virtual void ContentsSizeChanged(LocalFrame*, const IntSize&) const = 0;
   virtual void PageScaleFactorChanged() const {}
   virtual float ClampPageScaleFactorToLimits(float scale) const {
     return scale;
   }
   virtual void MainFrameScrollOffsetChanged() const {}
+  virtual void ResizeAfterLayout(LocalFrame*) const {}
   virtual void LayoutUpdated(LocalFrame*) const {}
 
   void MouseDidMoveOverElement(LocalFrame&, const HitTestResult&);
   virtual void SetToolTip(LocalFrame&, const String&, TextDirection) = 0;
   void ClearToolTip(LocalFrame&);
 
   bool Print(LocalFrame*);
 
   virtual void AnnotatedRegionsChanged() = 0;
 
@@ skipping 158 matching lines @@
   WeakMember<Node> last_mouse_over_node_;
   LayoutPoint last_tool_tip_point_;
   String last_tool_tip_text_;
 
   FRIEND_TEST_ALL_PREFIXES(ChromeClientTest, SetToolTipFlood);
 };
 
 }  // namespace blink
 
 #endif  // ChromeClient_h