sync: use progress markers instead of timestamps during GetUpdates

chrome/browser/sync/profile_sync_service_harness.h

 // Copyright (c) 2010 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_PROFILE_SYNC_SERVICE_HARNESS_H_
 #define CHROME_BROWSER_SYNC_PROFILE_SYNC_SERVICE_HARNESS_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 157 matching lines @@
   // Returns true if the sync client has no unsynced items.
   bool IsSynced();
 
   // Returns true if this client has downloaded all the items that the
   // other client has.
   bool MatchesOtherClient(ProfileSyncServiceHarness* partner);
 
   // Logs message with relevant info about client's sync state (if available).
   void LogClientInfo(std::string message);
 
-  // Gets the current progress indicator of the current sync session.
-  int64 GetUpdatedTimestamp();
+  // Gets the current progress indicator of the current sync session
+  // for a particular datatype.
+  std::string GetUpdatedTimestamp(syncable::ModelType model_type);
 
   WaitState wait_state_;
 
   Profile* profile_;
   ProfileSyncService* service_;
 
   // The harness of the client whose update progress marker we're expecting
   // eventually match.
   ProfileSyncServiceHarness* timestamp_match_partner_;
 
   // Credentials used for GAIA authentication.
   std::string username_;
   std::string password_;
 
   // Client ID, used for logging purposes.
   int id_;
 
   DISALLOW_COPY_AND_ASSIGN(ProfileSyncServiceHarness);
 };
 
 #endif  // CHROME_BROWSER_SYNC_PROFILE_SYNC_SERVICE_HARNESS_H_