Have Document::accessSVGExtensions() return a reference

Source/core/rendering/svg/RenderSVGResourceContainer.h

 /*
  * Copyright (C) Research In Motion Limited 2010. 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 73 matching lines @@
 
     HashSet<RenderObject*> m_clients;
     HashSet<RenderLayer*> m_clientLayers;
 };
 
 inline RenderSVGResourceContainer* getRenderSVGResourceContainerById(Document& document, const AtomicString& id)
 {
     if (id.isEmpty())
         return 0;
 
-    if (RenderSVGResourceContainer* renderResource = document.accessSVGExtensions()->resourceById(id))
+    if (RenderSVGResourceContainer* renderResource = document.accessSVGExtensions().resourceById(id))
         return renderResource;
 
     return 0;
 }
 
 template<typename Renderer>
 Renderer* getRenderSVGResourceById(Document& document, const AtomicString& id)
 {
     if (RenderSVGResourceContainer* container = getRenderSVGResourceContainerById(document, id))
         return container->cast<Renderer>();
 
     return 0;
 }
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderSVGResourceContainer, isSVGResourceContainer());
 
 }
 
 #endif