Replace more ObserverList with base::ObserverList.

sync/internal_api/sync_rollback_manager_base.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 SYNC_INTERNAL_API_SYNC_ROLLBACK_MANAGER_BASE_H_
 #define SYNC_INTERNAL_API_SYNC_ROLLBACK_MANAGER_BASE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 74 matching lines @@
       const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
       syncable::BaseTransaction* trans,
       std::vector<int64>* entries_changed) override;
 
   // syncable::TransactionObserver implementation.
   void OnTransactionWrite(
       const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
       ModelTypeSet models_with_changes) override;
 
  protected:
-  ObserverList<SyncManager::Observer>* GetObservers();
+  base::ObserverList<SyncManager::Observer>* GetObservers();
 
   // Initialize sync backup DB.
   bool InitInternal(
       const base::FilePath& database_location,
       InternalComponentsFactory* internal_components_factory,
       InternalComponentsFactory::StorageOption storage,
       scoped_ptr<UnrecoverableErrorHandler> unrecoverable_error_handler,
       ReportUnrecoverableErrorFunction report_unrecoverable_error_function);
 
   void RegisterDirectoryTypeDebugInfoObserver(
@@ skipping 13 matching lines @@
   void NotifyInitializationFailure();
 
   bool InitBackupDB(const base::FilePath& sync_folder,
                     InternalComponentsFactory* internal_components_factory,
                     InternalComponentsFactory::StorageOption storage);
 
   bool InitTypeRootNode(ModelType type);
   void InitBookmarkFolder(const std::string& folder);
 
   UserShare share_;
-  ObserverList<SyncManager::Observer> observers_;
+  base::ObserverList<SyncManager::Observer> observers_;
 
   scoped_ptr<UnrecoverableErrorHandler> unrecoverable_error_handler_;
   ReportUnrecoverableErrorFunction report_unrecoverable_error_function_;
 
   scoped_ptr<SyncEncryptionHandler> dummy_handler_;
 
   bool initialized_;
 
   base::WeakPtrFactory<SyncRollbackManagerBase> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncRollbackManagerBase);
 };
 
 }  // namespace syncer
 
 #endif  // SYNC_INTERNAL_API_SYNC_ROLLBACK_MANAGER_BASE_H_