Replace more ObserverList with base::ObserverList.

components/metrics/metrics_service.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.
 
 // This file defines a service that collects information about the user
 // experience in order to help improve future versions of the app.
 
 #ifndef COMPONENTS_METRICS_METRICS_SERVICE_H_
 #define COMPONENTS_METRICS_METRICS_SERVICE_H_
 
@@ skipping 456 matching lines @@
   // Stores the time of the first call to |GetUptimes()|.
   base::TimeTicks first_updated_time_;
 
   // Stores the time of the last call to |GetUptimes()|.
   base::TimeTicks last_updated_time_;
 
   // Field trial groups that map to Chrome configuration states.
   SyntheticTrialGroups synthetic_trial_groups_;
 
   // List of observers of |synthetic_trial_groups_| changes.
-  ObserverList<SyntheticTrialObserver> synthetic_trial_observer_list_;
+  base::ObserverList<SyntheticTrialObserver> synthetic_trial_observer_list_;
 
   // Execution phase the browser is in.
   static ExecutionPhase execution_phase_;
 
   // Reduntant marker to check that we completed our shutdown, and set the
   // exited-cleanly bit in the prefs.
   static ShutdownCleanliness clean_shutdown_status_;
 
   FRIEND_TEST_ALL_PREFIXES(MetricsServiceTest, IsPluginProcess);
   FRIEND_TEST_ALL_PREFIXES(MetricsServiceTest,
                            PermutedEntropyCacheClearedWhenLowEntropyReset);
   FRIEND_TEST_ALL_PREFIXES(MetricsServiceTest, RegisterSyntheticTrial);
 
   // Weak pointers factory used to post task on different threads. All weak
   // pointers managed by this factory have the same lifetime as MetricsService.
   base::WeakPtrFactory<MetricsService> self_ptr_factory_;
 
   // Weak pointers factory used for saving state. All weak pointers managed by
   // this factory are invalidated in ScheduleNextStateSave.
   base::WeakPtrFactory<MetricsService> state_saver_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MetricsService);
 };
 
 }  // namespace metrics
 
 #endif  // COMPONENTS_METRICS_METRICS_SERVICE_H_