Rename rendering/RenderScrollbar* to layout/LayoutScrollbar*

public/platform/WebScrollbarThemePainter.h

 /*
  * 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
@@ skipping 55 matching lines @@
 private:
     // The theme is not owned by this class. It is assumed that the theme is a
     // static pointer and its lifetime is essentially infinite. The functions
     // called from the painter may not be thread-safe, so all calls must be made
     // from the same thread that it is created on.
     ScrollbarTheme* m_theme;
 
     // It is assumed that the constructor of this paint object is responsible
     // for the lifetime of this scrollbar. The painter has to use the real
     // scrollbar (and not a WebScrollbar wrapper) due to static_casts for
-    // RenderScrollbar and pointer-based HashMap lookups for Lion scrollbars.
+    // LayoutScrollbar and pointer-based HashMap lookups for Lion scrollbars.
     Scrollbar* m_scrollbar;
 };
 
 } // namespace blink
 
 #endif