Update web classes to use OVERRIDE / FINAL when needed

Source/web/LocalFileSystemClient.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 18 matching lines @@
  */
 
 #ifndef LocalFileSystemClient_h
 #define LocalFileSystemClient_h
 
 #include "modules/filesystem/FileSystemClient.h"
 #include "wtf/Forward.h"
 
 namespace blink {
 
-class LocalFileSystemClient : public WebCore::FileSystemClient {
+class LocalFileSystemClient FINAL : public WebCore::FileSystemClient {
 public:
     static PassOwnPtr<FileSystemClient> create();
 
     virtual ~LocalFileSystemClient();
 
     virtual bool allowFileSystem(WebCore::ExecutionContext*) OVERRIDE;
 
 private:
     LocalFileSystemClient();
 };
 
 } // namespace blink
 
 #endif // LocalFileSystemClient_h