Move Singleton and related structs to namespace base

chrome/browser/extensions/window_controller_list.h

 // Copyright (c) 2012 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_EXTENSIONS_WINDOW_CONTROLLER_LIST_H_
 #define CHROME_BROWSER_EXTENSIONS_WINDOW_CONTROLLER_LIST_H_
 
 #include <list>
 
 #include "base/compiler_specific.h"
@@ skipping 51 matching lines @@
   // was invoked in using |filter|.
   WindowController* CurrentWindowForFunctionWithFilter(
       const UIThreadExtensionFunction* function,
       WindowController::TypeFilter filter) const;
 
   const ControllerList& windows() const { return windows_; }
 
   static WindowControllerList* GetInstance();
 
  private:
-  friend struct DefaultSingletonTraits<WindowControllerList>;
+  friend struct base::DefaultSingletonTraits<WindowControllerList>;
 
   // Entries are not owned by this class and must be removed when destroyed.
   ControllerList windows_;
 
   base::ObserverList<WindowControllerListObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowControllerList);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_WINDOW_CONTROLLER_LIST_H_