Update CSS classes to use OVERRIDE / FINAL when needed

Source/core/css/CSSMediaRule.h

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * (C) 2002-2003 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2002, 2006, 2008, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Samuel Weinig (sam@webkit.org)
  *
  * 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 12 matching lines @@
 #ifndef CSSMediaRule_h
 #define CSSMediaRule_h
 
 #include "core/css/CSSGroupingRule.h"
 #include "core/css/MediaList.h"
 
 namespace WebCore {
 
 class StyleRuleMedia;
 
-class CSSMediaRule : public CSSGroupingRule {
+class CSSMediaRule FINAL : public CSSGroupingRule {
 public:
     static PassRefPtr<CSSMediaRule> create(StyleRuleMedia* rule, CSSStyleSheet* sheet) { return adoptRef(new CSSMediaRule(rule, sheet)); }
 
     virtual ~CSSMediaRule();
 
     virtual CSSRule::Type type() const OVERRIDE { return MEDIA_RULE; }
     virtual void reattach(StyleRuleBase*) OVERRIDE;
     virtual String cssText() const OVERRIDE;
 
     MediaList* media() const;
 
 private:
     CSSMediaRule(StyleRuleMedia*, CSSStyleSheet*);
 
     MediaQuerySet* mediaQueries() const;
 
     mutable RefPtr<MediaList> m_mediaCSSOMWrapper;
 };
 
 DEFINE_CSS_RULE_TYPE_CASTS(CSSMediaRule, MEDIA_RULE);
 
 } // namespace WebCore
 
 #endif // CSSMediaRule_h