Update web classes to use OVERRIDE / FINAL when needed

Source/web/ExternalDateTimeChooser.h

 /*
  * Copyright (C) 2012 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:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 21 matching lines @@
 namespace WebCore {
 class DateTimeChooserClient;
 }
 
 namespace blink {
 
 class ChromeClientImpl;
 class WebString;
 class WebViewClient;
 
-class ExternalDateTimeChooser : public WebCore::DateTimeChooser {
+class ExternalDateTimeChooser FINAL : public WebCore::DateTimeChooser {
 public:
     static PassRefPtr<ExternalDateTimeChooser> create(ChromeClientImpl*, WebViewClient*, WebCore::DateTimeChooserClient*, const WebCore::DateTimeChooserParameters&);
     virtual ~ExternalDateTimeChooser();
 
     // The following functions are for DateTimeChooserCompletion.
     void didChooseValue(const WebString&);
     void didChooseValue(double);
     void didCancelChooser();
 
 private:
     ExternalDateTimeChooser(WebCore::DateTimeChooserClient*);
     bool openDateTimeChooser(ChromeClientImpl*, WebViewClient*, const WebCore::DateTimeChooserParameters&);
 
     // DateTimeChooser function:
     virtual void endChooser() OVERRIDE;
 
     WebCore::DateTimeChooserClient* m_client;
 };
 
 }
 #endif
 
 #endif