[Sync] Create UserEventSyncBridge.

components/sync/device_info/device_info_sync_bridge.h

 // Copyright 2015 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 COMPONENTS_SYNC_DEVICE_INFO_DEVICE_INFO_SYNC_BRIDGE_H_
 #define COMPONENTS_SYNC_DEVICE_INFO_DEVICE_INFO_SYNC_BRIDGE_H_
 
 #include <map>
 #include <memory>
 #include <string>
@@ skipping 110 matching lines @@
 
   ClientIdToSpecifics all_data_;
 
   // Registered observers, not owned.
   base::ObserverList<Observer, true> observers_;
 
   // Used to listen for provider initialization. If the provider is already
   // initialized during our constructor then the subscription is never used.
   std::unique_ptr<LocalDeviceInfoProvider::Subscription> subscription_;
 
-  // In charge of actually persiting changes to disk, or loading previous data.
+  // In charge of actually persisting changes to disk, or loading previous data.
   std::unique_ptr<ModelTypeStore> store_;
 
   // If |local_device_info_provider_| has initialized.
   bool has_provider_initialized_ = false;
   // If data has been loaded from the store.
   bool has_data_loaded_ = false;
 
   // Used to update our local device info once every pulse interval.
   base::OneShotTimer pulse_timer_;
 
   DISALLOW_COPY_AND_ASSIGN(DeviceInfoSyncBridge);
 };
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_DEVICE_INFO_DEVICE_INFO_SYNC_BRIDGE_H_