Have Node::document() return a reference instead of a pointer

Source/core/svg/SVGPolyElement.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007 Rob Buis <buis@kde.org>
  *
  * 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,
@@ skipping 64 matching lines @@
 void SVGPolyElement::parseAttribute(const QualifiedName& name, const AtomicString& value)
 {
     if (!isSupportedAttribute(name)) {
         SVGGraphicsElement::parseAttribute(name, value);
         return;
     }
 
     if (name == SVGNames::pointsAttr) {
         SVGPointList newList;
         if (!pointsListFromSVGData(newList, value))
-            document()->accessSVGExtensions()->reportError("Problem parsing points=\"" + value + "\"");
+            document().accessSVGExtensions()->reportError("Problem parsing points=\"" + value + "\"");
 
         if (SVGAnimatedProperty* wrapper = SVGAnimatedProperty::lookupWrapper<SVGPolyElement, SVGAnimatedPointList>(this, pointsPropertyInfo()))
             static_cast<SVGAnimatedPointList*>(wrapper)->detachListWrappers(newList.size());
 
         m_points.value = newList;
         return;
     }
 
     if (SVGLangSpace::parseAttribute(name, value))
         return;
@@ skipping 53 matching lines @@
     return static_cast<SVGListPropertyTearOff<SVGPointList>*>(static_pointer_cast<SVGAnimatedPointList>(lookupOrCreatePointsWrapper(this))->baseVal());
 }
 
 SVGListPropertyTearOff<SVGPointList>* SVGPolyElement::animatedPoints()
 {
     m_points.shouldSynchronize = true;
     return static_cast<SVGListPropertyTearOff<SVGPointList>*>(static_pointer_cast<SVGAnimatedPointList>(lookupOrCreatePointsWrapper(this))->animVal());
 }
 
 }