Add infrastructure for partial layouts

Source/core/rendering/RenderRubyBase.h

 /*
  * Copyright (C) 2009 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 37 matching lines @@
     virtual bool isRubyBase() const { return true; }
 
     virtual bool isChildAllowed(RenderObject*, RenderStyle*) const;
 
 private:
     RenderRubyBase();
 
     virtual ETextAlign textAlignmentForLine(bool endsWithSoftBreak) const;
     virtual void adjustInlineDirectionLineBounds(int expansionOpportunityCount, float& logicalLeft, float& logicalWidth) const;
 
+    virtual bool supportsPartialLayout() const OVERRIDE { return false; }
+
     void moveChildren(RenderRubyBase* toBase, RenderObject* beforeChild = 0);
     void moveInlineChildren(RenderRubyBase* toBase, RenderObject* beforeChild = 0);
     void moveBlockChildren(RenderRubyBase* toBase, RenderObject* beforeChild = 0);
 
     RenderRubyRun* rubyRun() const;
 
     // Allow RenderRubyRun to manipulate the children within ruby bases.
     friend class RenderRubyRun;
 };
 
 } // namespace WebCore
 
 #endif // RenderRubyBase_h