[sync] Add backup time in synced device info so that server can flag device

chrome/browser/sync/glue/synced_device_tracker.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_SYNC_GLUE_SYNCED_DEVICE_TRACKER_H_
 #define CHROME_BROWSER_SYNC_GLUE_SYNCED_DEVICE_TRACKER_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 43 matching lines @@
       ScopedVector<DeviceInfo>* device_info) const;
 
   virtual std::string cache_guid() const;
 
   // Can be called on any thread. Will be notified back on the same thread
   // they were called on. Observer will be called on every device info
   // change.
   void AddObserver(Observer* observer);
   void RemoveObserver(Observer* observer);
 
+  // Update |backup_timestamp| in local device info specifics to |backup_time|
+  // if different.
+  void UpdateLocalDeviceBackupTime(base::Time backup_time);
+
+  // Return time derived from |backup_timestamp| in local device info specifics.
+  base::Time GetLocalDeviceBackupTime() const;
+
  private:
   friend class SyncedDeviceTrackerTest;
 
   void InitLocalDeviceInfoContinuation(const base::Closure& callback,
                                        const DeviceInfo& local_info);
 
   // Helper to write specifics into our node.  Also useful for testing.
   void WriteLocalDeviceInfo(const DeviceInfo& info);
 
   // Helper to write arbitrary device info. Useful for writing local device
   // info and also used by test cases to write arbitrary device infos.
-  void WriteDeviceInfo(const sync_pb::DeviceInfoSpecifics& specifics,
-                       const std::string& tag);
+  void WriteDeviceInfo(const DeviceInfo& info, const std::string& tag);
 
   syncer::UserShare* user_share_;
   const std::string cache_guid_;
   const std::string local_device_info_tag_;
 
   // The |ObserverList| has to be thread safe as the changes happen
   // on sync thread and the observers could be on any thread.
   typedef ObserverListThreadSafe<Observer> ObserverList;
   scoped_refptr<ObserverList> observers_;
 
   base::WeakPtrFactory<SyncedDeviceTracker> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncedDeviceTracker);
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_GLUE_SYNCED_DEVICE_TRACKER_H_