Move Singleton and related structs to namespace base

chrome/browser/predictors/autocomplete_action_predictor_factory.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_PREDICTORS_AUTOCOMPLETE_ACTION_PREDICTOR_FACTORY_H_
 #define CHROME_BROWSER_PREDICTORS_AUTOCOMPLETE_ACTION_PREDICTOR_FACTORY_H_
 
 #include "base/basictypes.h"
 #include "base/memory/singleton.h"
 #include "components/keyed_service/content/browser_context_keyed_service_factory.h"
 
 class Profile;
 
 namespace predictors {
 
 class AutocompleteActionPredictor;
 
 // Singleton that owns all AutocompleteActionPredictors and associates them with
 // Profiles. Listens for the Profile's destruction notification and cleans up
 // the associated AutocompleteActionPredictor.
 class AutocompleteActionPredictorFactory
     : public BrowserContextKeyedServiceFactory {
  public:
   static AutocompleteActionPredictor* GetForProfile(Profile* profile);
 
   static AutocompleteActionPredictorFactory* GetInstance();
 
  private:
-  friend struct DefaultSingletonTraits<AutocompleteActionPredictorFactory>;
+  friend struct base::DefaultSingletonTraits<
+      AutocompleteActionPredictorFactory>;
 
   AutocompleteActionPredictorFactory();
   ~AutocompleteActionPredictorFactory() override;
 
   // BrowserContextKeyedServiceFactory:
   content::BrowserContext* GetBrowserContextToUse(
       content::BrowserContext* context) const override;
   KeyedService* BuildServiceInstanceFor(
       content::BrowserContext* profile) const override;
 
   DISALLOW_COPY_AND_ASSIGN(AutocompleteActionPredictorFactory);
 };
 
 }  // namespace predictors
 
 #endif  // CHROME_BROWSER_PREDICTORS_AUTOCOMPLETE_ACTION_PREDICTOR_FACTORY_H_