Pass implementation object to supplemental classes by reference

Source/core/svg/SVGDocument.cpp

 /*
  * Copyright (C) 2004, 2005 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 21 matching lines @@
 #include "core/svg/SVGZoomAndPan.h"
 #include "core/svg/SVGZoomEvent.h"
 
 namespace WebCore {
 
 SVGDocument::SVGDocument(const DocumentInit& initializer)
     : XMLDocument(initializer, XMLDocumentClass | SVGDocumentClass)
 {
 }
 
-SVGSVGElement* SVGDocument::rootElement(const Document* document)
+SVGSVGElement* SVGDocument::rootElement(const Document& document)
 {
-    Element* elem = document->documentElement();
+    Element* elem = document.documentElement();
     if (elem && elem->hasTagName(SVGNames::svgTag))
         return toSVGSVGElement(elem);
 
     return 0;
 }
 
 SVGSVGElement* SVGDocument::rootElement() const
 {
-    return rootElement(this);
+    return rootElement(*this);
 }
 
 void SVGDocument::dispatchZoomEvent(float prevScale, float newScale)
 {
     RefPtr<SVGZoomEvent> event = SVGZoomEvent::create();
     event->initEvent(EventTypeNames::zoom, true, false);
     event->setPreviousScale(prevScale);
     event->setNewScale(newScale);
     rootElement()->dispatchEvent(event.release(), IGNORE_EXCEPTION);
 }
@@ skipping 33 matching lines @@
             renderer()->repaint();
     }
 }
 
 PassRefPtr<Document> SVGDocument::cloneDocumentWithoutChildren()
 {
     return create(DocumentInit(url()));
 }
 
 }