Update CSS classes to use OVERRIDE / FINAL when needed

Source/core/css/StyleRuleImport.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.
  *
  * 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 36 matching lines @@
     StyleSheetContents* styleSheet() const { return m_styleSheet.get(); }
 
     bool isLoading() const;
     MediaQuerySet* mediaQueries() { return m_mediaQueries.get(); }
 
     void requestStyleSheet();
 
 private:
     // NOTE: We put the StyleSheetResourceClient in a member instead of inheriting from it
     // to avoid adding a vptr to StyleRuleImport.
-    class ImportedStyleSheetClient : public StyleSheetResourceClient {
+    class ImportedStyleSheetClient FINAL : public StyleSheetResourceClient {
     public:
         ImportedStyleSheetClient(StyleRuleImport* ownerRule) : m_ownerRule(ownerRule) { }
         virtual ~ImportedStyleSheetClient() { }
-        virtual void setCSSStyleSheet(const String& href, const KURL& baseURL, const String& charset, const CSSStyleSheetResource* sheet)
+        virtual void setCSSStyleSheet(const String& href, const KURL& baseURL, const String& charset, const CSSStyleSheetResource* sheet) OVERRIDE
         {
             m_ownerRule->setCSSStyleSheet(href, baseURL, charset, sheet);
         }
     private:
         StyleRuleImport* m_ownerRule;
     };
 
     void setCSSStyleSheet(const String& href, const KURL& baseURL, const String& charset, const CSSStyleSheetResource*);
     friend class ImportedStyleSheetClient;
 
     StyleRuleImport(const String& href, PassRefPtr<MediaQuerySet>);
 
     StyleSheetContents* m_parentStyleSheet;
 
     ImportedStyleSheetClient m_styleSheetClient;
     String m_strHref;
     RefPtr<MediaQuerySet> m_mediaQueries;
     RefPtr<StyleSheetContents> m_styleSheet;
     ResourcePtr<CSSStyleSheetResource> m_resource;
     bool m_loading;
 };
 
 DEFINE_STYLE_RULE_TYPE_CASTS(Import);
 
 } // namespace WebCore
 
 #endif