Remove #pragma once from sync

sync/engine/store_timestamps_command.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 SYNC_ENGINE_STORE_TIMESTAMPS_COMMAND_H_
 #define SYNC_ENGINE_STORE_TIMESTAMPS_COMMAND_H_
-#pragma once
 
 #include "base/compiler_specific.h"
 #include "sync/engine/syncer_command.h"
 #include "sync/engine/syncer_types.h"
 
 namespace syncer {
 
 // A syncer command that extracts the changelog timestamp information from
 // a GetUpdatesResponse (fetched in DownloadUpdatesCommand) and stores
 // it in the directory.  This is meant to run immediately after
@@ skipping 14 matching lines @@
   // SyncerCommand implementation.
   virtual SyncerError ExecuteImpl(sessions::SyncSession* session) OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(StoreTimestampsCommand);
 };
 
 }  // namespace syncer
 
 #endif  // SYNC_ENGINE_STORE_TIMESTAMPS_COMMAND_H_