Initial touch-action main thread implementation

Source/core/dom/Node.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * 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 507 matching lines @@
     virtual bool canStartSelection() const;
 
     // Getting points into and out of screen space
     FloatPoint convertToPage(const FloatPoint&) const;
     FloatPoint convertFromPage(const FloatPoint&) const;
 
     // -----------------------------------------------------------------------------
     // Integration with rendering tree
 
     // As renderer() includes a branch you should avoid calling it repeatedly in hot code paths.
+    // Note that if a Node has a renderer, it's parentNode is guaranteed to have one as well.
     RenderObject* renderer() const { return hasRareData() ? m_data.m_rareData->renderer() : m_data.m_renderer; };
     void setRenderer(RenderObject* renderer)
     {
         if (hasRareData())
             m_data.m_rareData->setRenderer(renderer);
         else
             m_data.m_renderer = renderer;
     }
     bool hasRenderer() const { return renderer(); }
 
@@ skipping 414 matching lines @@
 
 } // namespace WebCore
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showTree(const WebCore::Node*);
 void showNodePath(const WebCore::Node*);
 #endif
 
 #endif