Don't repaint when setting border or outline 0 with style none

Source/core/rendering/style/RenderStyle.cpp

 /*
  * Copyright (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Adobe Systems Incorporated. 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 604 matching lines @@
         changedContextSensitiveProperties |= ContextSensitivePropertyFilter;
     }
 
     if (rareNonInheritedData->m_mask != other.rareNonInheritedData->m_mask
         || rareNonInheritedData->m_maskBoxImage != other.rareNonInheritedData->m_maskBoxImage)
         return StyleDifferenceRepaintLayer;
 
     if (inherited_flags._visibility != other.inherited_flags._visibility
         || inherited_flags.m_printColorAdjust != other.inherited_flags.m_printColorAdjust
         || inherited_flags._insideLink != other.inherited_flags._insideLink
-        || surround->border != other.surround->border
-        || *m_background.get() != *other.m_background.get()
+        || !surround->border.visuallyEqual(other.surround->border)
+        || !m_background->visuallyEqual(*other.m_background)
         || rareInheritedData->userModify != other.rareInheritedData->userModify
         || rareInheritedData->userSelect != other.rareInheritedData->userSelect
         || rareNonInheritedData->userDrag != other.rareNonInheritedData->userDrag
         || rareNonInheritedData->m_borderFit != other.rareNonInheritedData->m_borderFit
         || rareNonInheritedData->m_objectFit != other.rareNonInheritedData->m_objectFit
         || rareNonInheritedData->m_objectPosition != other.rareNonInheritedData->m_objectPosition
         || rareInheritedData->m_imageRendering != other.rareInheritedData->m_imageRendering)
         return StyleDifferenceRepaint;
 
         // FIXME: The current spec is being reworked to remove dependencies between exclusions and affected
@@ skipping 1017 matching lines @@
     // right
     radiiSum = radii.topRight().height() + radii.bottomRight().height();
     if (radiiSum > rect.height())
         factor = std::min(rect.height() / radiiSum, factor);
 
     ASSERT(factor <= 1);
     return factor;
 }
 
 } // namespace WebCore