FINALizing of the Node hierarchy.

Source/core/html/HTMLHeadingElement.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2010 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */
 
 #ifndef HTMLHeadingElement_h
 #define HTMLHeadingElement_h
 
 #include "HTMLElement.h"
 
 namespace WebCore {
 
-class HTMLHeadingElement : public HTMLElement {
+class HTMLHeadingElement FINAL : public HTMLElement {
 public:
     static PassRefPtr<HTMLHeadingElement> create(const QualifiedName&, Document*);
 
 private:
     HTMLHeadingElement(const QualifiedName&, Document*);
 };
 
 } // namespace WebCore
 
 #endif // HTMLHeadingElement_h