[sync] Set up notification-free infra for triggering local sync refresh

chrome/browser/sync/glue/sync_backend_host_impl.h

 // Copyright 2013 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_SYNC_BACKEND_HOST_IMPL_H_
 #define CHROME_BROWSER_SYNC_GLUE_SYNC_BACKEND_HOST_IMPL_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 81 matching lines @@
       const std::string& sync_user_agent,
       const syncer::SyncCredentials& credentials,
       bool delete_sync_data_folder,
       scoped_ptr<syncer::SyncManagerFactory> sync_manager_factory,
       const syncer::WeakHandle<syncer::UnrecoverableErrorHandler>&
           unrecoverable_error_handler,
       const base::Closure& report_unrecoverable_error_function,
       syncer::NetworkResources* network_resources,
       scoped_ptr<syncer::SyncEncryptionHandler::NigoriState> saved_nigori_state)
       override;
+  void TriggerRefresh(const syncer::ModelTypeSet& types) override;
   void UpdateCredentials(const syncer::SyncCredentials& credentials) override;
   void StartSyncingWithServer() override;
   void SetEncryptionPassphrase(const std::string& passphrase,
                                bool is_explicit) override;
   bool SetDecryptionPassphrase(const std::string& passphrase) override
       WARN_UNUSED_RESULT;
   void StopSyncingForShutdown() override;
   scoped_ptr<base::Thread> Shutdown(syncer::ShutdownReason reason) override;
   void UnregisterInvalidationIds() override;
   syncer::ModelTypeSet ConfigureDataTypes(
@@ skipping 274 matching lines @@
   bool invalidation_handler_registered_;
 
   base::WeakPtrFactory<SyncBackendHostImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncBackendHostImpl);
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_GLUE_SYNC_BACKEND_HOST_IMPL_H_