Move Singleton and related structs to namespace base

chrome/browser/chromeos/file_system_provider/service_factory.h

 // Copyright 2014 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_CHROMEOS_FILE_SYSTEM_PROVIDER_SERVICE_FACTORY_H_
 #define CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_SERVICE_FACTORY_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 14 matching lines @@
   static Service* Get(content::BrowserContext* context);
 
   // Returns a service instance for the context if exists. Otherwise, returns
   // NULL.
   static Service* FindExisting(content::BrowserContext* context);
 
   // Gets a singleton instance of the factory.
   static ServiceFactory* GetInstance();
 
  private:
-  friend struct DefaultSingletonTraits<ServiceFactory>;
+  friend struct base::DefaultSingletonTraits<ServiceFactory>;
 
   ServiceFactory();
   ~ServiceFactory() override;
 
   // BrowserContextKeyedServiceFactory overrides:
   KeyedService* BuildServiceInstanceFor(
       content::BrowserContext* profile) const override;
   bool ServiceIsCreatedWithBrowserContext() const override;
   content::BrowserContext* GetBrowserContextToUse(
       content::BrowserContext* context) const override;
 
   DISALLOW_COPY_AND_ASSIGN(ServiceFactory);
 };
 
 }  // namespace file_system_provider
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_SERVICE_FACTORY_H_