Move Singleton and related structs to namespace base

chrome/browser/search/instant_service_factory.h

 // Copyright 2013 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_SEARCH_INSTANT_SERVICE_FACTORY_H_
 #define CHROME_BROWSER_SEARCH_INSTANT_SERVICE_FACTORY_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/singleton.h"
 #include "components/keyed_service/content/browser_context_keyed_service_factory.h"
 
 class InstantService;
 class Profile;
 
 // Singleton that owns all InstantServices and associates them with Profiles.
 class InstantServiceFactory : public BrowserContextKeyedServiceFactory {
  public:
   // Returns the InstantService for |profile|.
   static InstantService* GetForProfile(Profile* profile);
 
   static InstantServiceFactory* GetInstance();
 
  private:
-  friend struct DefaultSingletonTraits<InstantServiceFactory>;
+  friend struct base::DefaultSingletonTraits<InstantServiceFactory>;
 
   InstantServiceFactory();
   ~InstantServiceFactory() override;
 
   // Overridden from BrowserContextKeyedServiceFactory:
   content::BrowserContext* GetBrowserContextToUse(
       content::BrowserContext* context) const override;
   KeyedService* BuildServiceInstanceFor(
       content::BrowserContext* profile) const override;
 
   DISALLOW_COPY_AND_ASSIGN(InstantServiceFactory);
 };
 
 #endif  // CHROME_BROWSER_SEARCH_INSTANT_SERVICE_FACTORY_H_