[SyncFS] Add RemoteToLocalSyncer skeleton

chrome/browser/sync_file_system/drive_backend/sync_engine_context.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_FILE_SYSTEM_DRIVE_BACKEND_SYNC_ENGINE_CONTEXT_H_
 #define CHROME_BROWSER_SYNC_FILE_SYSTEM_DRIVE_BACKEND_SYNC_ENGINE_CONTEXT_H_
 
 #include "base/basictypes.h"
 
 namespace drive {
 class DriveServiceInterface;
 }
 
 namespace sync_file_system {
+
+class RemoteChangeProcessor;
+
 namespace drive_backend {
 
 class MetadataDatabase;
 
 class SyncEngineContext {
  public:
   SyncEngineContext() {}
   ~SyncEngineContext() {}
 
   virtual drive::DriveServiceInterface* GetDriveService() = 0;
   virtual MetadataDatabase* GetMetadataDatabase() = 0;
+  virtual RemoteChangeProcessor* GetRemoteChangeProcessor() = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SyncEngineContext);
 };
 
 }  // namespace drive_backend
 }  // namespace sync_file_system
 
 #endif  // CHROME_BROWSER_SYNC_FILE_SYSTEM_DRIVE_BACKEND_SYNC_ENGINE_CONTEXT_H_