Replace more ObserverList with base::ObserverList.

components/invalidation/sync_system_resources.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.
 //
 // Simple system resources class that uses the current message loop
 // for scheduling.  Assumes the current message loop is already
 // running.
 
 #ifndef COMPONENTS_INVALIDATION_SYNC_SYSTEM_RESOURCES_H_
 #define COMPONENTS_INVALIDATION_SYNC_SYSTEM_RESOURCES_H_
@@ skipping 153 matching lines @@
 
   // Callbacks into invalidation library
   scoped_ptr<invalidation::MessageCallback> incoming_receiver_;
   NetworkStatusReceiverList network_status_receivers_;
 
   // Last network status for new network status receivers.
   bool last_network_status_;
 
   int received_messages_count_;
 
-  ObserverList<Observer> observers_;
+  base::ObserverList<Observer> observers_;
 };
 
 class SyncStorage : public invalidation::Storage {
  public:
   SyncStorage(StateWriter* state_writer, invalidation::Scheduler* scheduler);
 
   ~SyncStorage() override;
 
   void SetInitialState(const std::string& value) {
     cached_state_ = value;
@@ skipping 55 matching lines @@
   scoped_ptr<SyncInvalidationScheduler> internal_scheduler_;
   scoped_ptr<SyncInvalidationScheduler> listener_scheduler_;
   scoped_ptr<SyncStorage> storage_;
   // sync_network_channel_ is owned by SyncInvalidationListener.
   SyncNetworkChannel* sync_network_channel_;
 };
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_INVALIDATION_SYNC_SYSTEM_RESOURCES_H_