Fix virtual/override/final usage in Source/core/dom/.

Source/core/dom/CharacterData.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 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 56 matching lines @@
     }
     enum UpdateSource {
         UpdateFromParser,
         UpdateFromNonParser,
     };
     void didModifyData(const String& oldValue, UpdateSource);
 
     String m_data;
 
 private:
-    virtual String nodeValue() const override final;
-    virtual void setNodeValue(const String&) override final;
-    virtual bool isCharacterDataNode() const override final { return true; }
-    virtual int maxCharacterOffset() const override final;
+    String nodeValue() const final;
+    void setNodeValue(const String&) final;
+    bool isCharacterDataNode() const final { return true; }
+    int maxCharacterOffset() const final;
     void setDataAndUpdate(const String&, unsigned offsetOfReplacedData, unsigned oldLength, unsigned newLength, UpdateSource = UpdateFromNonParser, RecalcStyleBehavior = DoNotRecalcStyle);
 
     bool isContainerNode() const = delete; // This will catch anyone doing an unnecessary check.
     bool isElementNode() const = delete; // This will catch anyone doing an unnecessary check.
 };
 
 DEFINE_NODE_TYPE_CASTS(CharacterData, isCharacterDataNode());
 
 } // namespace blink
 
 #endif // CharacterData_h