Remove Node.prefix so it's no longer visible to script.

Source/core/dom/Attr.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 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
@@ skipping 45 matching lines @@
 
     const QualifiedName& qualifiedName() const { return m_name; }
 
     bool isId() const;
 
     void attachToElement(Element*);
     void detachFromElementWithValue(const AtomicString&);
 
     virtual const AtomicString& localName() const OVERRIDE { return m_name.localName(); }
     virtual const AtomicString& namespaceURI() const OVERRIDE { return m_name.namespaceURI(); }
-    virtual const AtomicString& prefix() const OVERRIDE { return m_name.prefix(); }
+    virtual const AtomicString& prefix() const OVERRIDE FINAL { return m_name.prefix(); }
 
-    virtual void setPrefix(const AtomicString&, ExceptionState&) OVERRIDE;
+    void setPrefix(const AtomicString&, ExceptionState&);
 
 private:
     Attr(Element&, const QualifiedName&);
     Attr(Document&, const QualifiedName&, const AtomicString& value);
 
     void createTextChild();
 
     virtual String nodeName() const OVERRIDE { return name(); }
     virtual NodeType nodeType() const OVERRIDE { return ATTRIBUTE_NODE; }
 
@@ skipping 14 matching lines @@
     QualifiedName m_name;
     AtomicString m_standaloneValue;
     unsigned m_ignoreChildrenChanged;
 };
 
 DEFINE_NODE_TYPE_CASTS(Attr, isAttributeNode());
 
 } // namespace WebCore
 
 #endif // Attr_h