Add OVERRIDE to chrome/browser/.

chrome/browser/plugin_data_remover_helper.h

 // 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.
 
 #ifndef CHROME_BROWSER_PLUGIN_DATA_REMOVER_HELPER_H_
 #define CHROME_BROWSER_PLUGIN_DATA_REMOVER_HELPER_H_
 #pragma once
 
 #include <vector>
 
@@ skipping 30 matching lines @@
 
   bool GetValue() const { return pref_.GetValue(); }
 
   // Like PluginDataRemover::IsSupported, but checks that the returned plugin
   // is enabled by PluginPrefs
   static bool IsSupported(PluginPrefs* plugin_prefs);
 
   // content::NotificationObserver methods:
   virtual void Observe(int type,
                        const content::NotificationSource& source,
-                       const content::NotificationDetails& details);
+                       const content::NotificationDetails& details) OVERRIDE;
 
  private:
   void StartUpdate();
   void GotPlugins(scoped_refptr<PluginPrefs> plugin_prefs,
                   const std::vector<webkit::WebPluginInfo>& plugins);
 
   BooleanPrefMember pref_;
   content::NotificationRegistrar registrar_;
   // Weak pointer.
   Profile* profile_;
   base::WeakPtrFactory<PluginDataRemoverHelper> factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PluginDataRemoverHelper);
 };
 
 #endif  // CHROME_BROWSER_PLUGIN_DATA_REMOVER_HELPER_H_