Drop SVGElement::isSVGSVGElement() virtual function

Source/core/svg/SVGSVGElement.h

 /*
  * Copyright (C) 2004, 2005, 2006 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2010 Rob Buis <buis@kde.org>
  * Copyright (C) 2014 Google, Inc.
  *
  * 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.
  *
@@ skipping 116 matching lines @@
 
     SVGAnimatedLength* x() const { return m_x.get(); }
     SVGAnimatedLength* y() const { return m_y.get(); }
     SVGAnimatedLength* width() const { return m_width.get(); }
     SVGAnimatedLength* height() const { return m_height.get(); }
 
 private:
     explicit SVGSVGElement(Document&);
     virtual ~SVGSVGElement();
 
-    virtual bool isSVGSVGElement() const OVERRIDE { return true; }
-
     virtual void parseAttribute(const QualifiedName&, const AtomicString&) OVERRIDE;
 
     virtual bool rendererIsNeeded(const RenderStyle&) OVERRIDE;
     virtual RenderObject* createRenderer(RenderStyle*) OVERRIDE;
 
     virtual InsertionNotificationRequest insertedInto(ContainerNode*) OVERRIDE;
     virtual void removedFrom(ContainerNode*) OVERRIDE;
 
     virtual void svgAttributeChanged(const QualifiedName&) OVERRIDE;
 
@@ skipping 22 matching lines @@
     RefPtr<SMILTimeContainer> m_timeContainer;
     RefPtr<SVGPoint> m_translation;
     RefPtr<SVGViewSpec> m_viewSpec;
 
     friend class SVGCurrentTranslateTearOff;
 };
 
 } // namespace WebCore
 
 #endif