Add OVERRIDE to chrome/renderer.

chrome/renderer/visitedlink_slave.h

Index: chrome/renderer/visitedlink_slave.h
diff --git a/chrome/renderer/visitedlink_slave.h b/chrome/renderer/visitedlink_slave.h
index 52110a15a2b2d10d81dd58f2291020f55cddedfa..6bae4fdf40612bff82b9a7858360aa299af2c1f5 100644
--- a/chrome/renderer/visitedlink_slave.h
+++ b/chrome/renderer/visitedlink_slave.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -6,6 +6,7 @@
 #define CHROME_RENDERER_VISITEDLINK_SLAVE_H_
 #pragma once
 
+#include "base/compiler_specific.h"
 #include "base/shared_memory.h"
 #include "chrome/common/visitedlink_common.h"
 #include "content/public/renderer/render_process_observer.h"
@@ -19,7 +20,7 @@ class VisitedLinkSlave : public VisitedLinkCommon,
   virtual ~VisitedLinkSlave();
 
   // RenderProcessObserver implementation.
-  virtual bool OnControlMessageReceived(const IPC::Message& message);
+  virtual bool OnControlMessageReceived(const IPC::Message& message) OVERRIDE;
 
   // Message handlers.
   void OnUpdateVisitedLinks(base::SharedMemoryHandle table);