Don't layout when isSelfPaintingLayer() changes

Source/core/rendering/RenderLayerModelObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2010, 2012 Google 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
@@ skipping 103 matching lines @@
             }
         }
     }
 
     RenderObject::styleWillChange(diff, newStyle);
 }
 
 void RenderLayerModelObject::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
 {
     bool hadTransform = hasTransform();
-    bool hadLayer = hasLayer();
-    bool layerWasSelfPainting = hadLayer && layer()->isSelfPaintingLayer();
 
     RenderObject::styleDidChange(diff, oldStyle);
     updateFromStyle();
 
     LayerType type = layerTypeRequired();
     if (type != NoLayer) {
         if (!layer() && layerCreationAllowedForSubtree()) {
             if (s_wasFloating && isFloating())
                 setChildNeedsLayout();
             createLayer(type);
@@ skipping 18 matching lines @@
         if (s_wasFloating && isFloating())
             setChildNeedsLayout();
         if (hadTransform)
             setNeedsLayoutAndPrefWidthsRecalc();
     }
 
     if (layer()) {
         // FIXME: Ideally we shouldn't need this setter but we can't easily infer an overflow-only layer
         // from the style.
         layer()->setLayerType(type);
-
         layer()->styleChanged(diff, oldStyle);
-        if (hadLayer && layer()->isSelfPaintingLayer() != layerWasSelfPainting)
-            setChildNeedsLayout();
     }
 
     if (FrameView *frameView = view()->frameView()) {
         bool newStyleIsViewportConstained = style()->hasViewportConstrainedPosition();
         bool oldStyleIsViewportConstrained = oldStyle && oldStyle->hasViewportConstrainedPosition();
         if (newStyleIsViewportConstained != oldStyleIsViewportConstrained) {
             if (newStyleIsViewportConstained && layer())
                 frameView->addViewportConstrainedObject(this);
             else
                 frameView->removeViewportConstrainedObject(this);
@@ skipping 29 matching lines @@
     return m_layer ? m_layer->hasCompositedLayerMapping() : false;
 }
 
 CompositedLayerMapping* RenderLayerModelObject::groupedMapping() const
 {
     return m_layer ? m_layer->groupedMapping() : 0;
 }
 
 } // namespace WebCore