Devirtualize Document class type checking

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 19 matching lines @@
 #include "core/rendering/RenderView.h"
 #include "core/svg/SVGElement.h"
 #include "core/svg/SVGSVGElement.h"
 #include "core/svg/SVGViewSpec.h"
 #include "core/svg/SVGZoomAndPan.h"
 #include "core/svg/SVGZoomEvent.h"
 
 namespace WebCore {
 
 SVGDocument::SVGDocument(Frame* frame, const KURL& url)
-    : Document(frame, url, false, false)
+    : Document(frame, url, SVGDocumentClass)
 {
     ScriptWrappable::init(this);
 }
 
 SVGSVGElement* SVGDocument::rootElement() const
 {
     Element* elem = documentElement();
     if (elem && elem->hasTagName(SVGNames::svgTag))
         return toSVGSVGElement(elem);
 
@@ skipping 48 matching lines @@
 {
     if (childContext.node()->hasTagName(SVGNames::svgTag))
         return toSVGSVGElement(childContext.node())->isValid();
     return true;
 }
 
 }
 
 // vim:ts=4:noet
 #endif // ENABLE(SVG)