Update fetch / loader classes to use OVERRIDE / FINAL when needed

Source/core/loader/PrerenderHandle.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 25 matching lines @@
 #include "wtf/Noncopyable.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/PassRefPtr.h"
 
 namespace WebCore {
 
 class Document;
 class Prerender;
 class PrerenderClient;
 
-class PrerenderHandle : public DocumentLifecycleObserver {
+class PrerenderHandle FINAL : public DocumentLifecycleObserver {
     WTF_MAKE_NONCOPYABLE(PrerenderHandle);
 public:
     static PassOwnPtr<PrerenderHandle> create(Document&, PrerenderClient*, const KURL&);
 
     virtual ~PrerenderHandle();
 
     void cancel();
     const KURL& url() const;
 
     // From DocumentLifecycleObserver:
     virtual void documentWasDetached() OVERRIDE;
 private:
     PrerenderHandle(Document&, PassRefPtr<Prerender>);
 
     void detach();
 
     RefPtr<Prerender> m_prerender;
 };
 
 }
 
 #endif // PrerenderHandle_h