Add Element::subResourceAttributeName() virtual function

Source/core/html/HTMLEmbedElement.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2006, 2008, 2009 Apple Inc. 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.
  *
@@ skipping 25 matching lines @@
 private:
     HTMLEmbedElement(Document&, bool createdByParser);
 
     virtual void parseAttribute(const QualifiedName&, const AtomicString&) OVERRIDE;
     virtual bool isPresentationAttribute(const QualifiedName&) const OVERRIDE;
     virtual void collectStyleForPresentationAttribute(const QualifiedName&, const AtomicString&, MutableStylePropertySet*) OVERRIDE;
 
     virtual bool rendererIsNeeded(const RenderStyle&) OVERRIDE;
 
     virtual bool isURLAttribute(const Attribute&) const OVERRIDE;
+    virtual const QualifiedName& subResourceAttributeName() const OVERRIDE;
     virtual const AtomicString imageSourceURL() const OVERRIDE;
 
     virtual RenderWidget* existingRenderWidget() const OVERRIDE;
 
     virtual void updateWidgetInternal() OVERRIDE;
 
     void parametersForPlugin(Vector<String>& paramNames, Vector<String>& paramValues);
 
     virtual bool shouldRegisterAsNamedItem() const OVERRIDE { return true; }
     virtual bool isInteractiveContent() const OVERRIDE;
 };
 
 }
 
 #endif