Use unified invalidation path for repaint-only style changes

Source/core/rendering/RenderBox.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2006, 2007 Apple Inc. 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 699 matching lines @@
 
     RenderBoxRareData& ensureRareData()
     {
         if (!m_rareData)
             m_rareData = adoptPtr(new RenderBoxRareData());
         return *m_rareData.get();
     }
 
     void savePreviousBorderBoxSizeIfNeeded();
 
+    void invalidatePaintIfNeeded(const PaintInvalidationState&, const RenderLayerModelObject& newPaintInvalidationContainer);
+
 private:
     // The width/height of the contents + borders + padding.  The x/y location is relative to our container (which is not always our parent).
     LayoutRect m_frameRect;
 
     // Our intrinsic height, used for min-height: min-content etc. Maintained by
     // updateLogicalHeight. This is logicalHeight() before it is clamped to
     // min/max.
     mutable LayoutUnit m_intrinsicContentLogicalHeight;
 
 protected:
@@ skipping 50 matching lines @@
         if (UNLIKELY(inlineBoxWrapper() != 0))
             deleteLineBoxWrapper();
     }
 
     ensureRareData().m_inlineBoxWrapper = boxWrapper;
 }
 
 } // namespace WebCore
 
 #endif // RenderBox_h