Fix virtual/override/final usage in Source/platform/.

Source/platform/exported/WebURLResponse.cpp

 /*
  * Copyright (C) 2009 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 31 matching lines @@
 #include "wtf/RefPtr.h"
 
 namespace blink {
 
 namespace {
 
 class ExtraDataContainer : public ResourceResponse::ExtraData {
 public:
     static PassRefPtr<ExtraDataContainer> create(WebURLResponse::ExtraData* extraData) { return adoptRef(new ExtraDataContainer(extraData)); }
 
-    virtual ~ExtraDataContainer() { }
+    ~ExtraDataContainer() override {}
 
     WebURLResponse::ExtraData* extraData() const { return m_extraData.get(); }
 
 private:
     explicit ExtraDataContainer(WebURLResponse::ExtraData* extraData)
         : m_extraData(adoptPtr(extraData))
     {
     }
 
     OwnPtr<WebURLResponse::ExtraData> m_extraData;
@@ skipping 406 matching lines @@
     // Subclasses may call this directly so a self-assignment check is needed
     // here as well as in the public assign method.
     if (m_private == p)
         return;
     if (m_private)
         m_private->dispose();
     m_private = p;
 }
 
 } // namespace blink