[SyncFS] Add RemoteToLocalSyncer skeleton

chrome/browser/sync_file_system/drive_backend/local_to_remote_syncer.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_LOCAL_TO_REMOTE_SYNCER_H_
 #define CHROME_BROWSER_SYNC_FILE_SYSTEM_DRIVE_BACKEND_LOCAL_TO_REMOTE_SYNCER_H_
 
+#include "base/memory/weak_ptr.h"
 #include "chrome/browser/sync_file_system/sync_callbacks.h"
 #include "chrome/browser/sync_file_system/sync_task.h"
 
 namespace sync_file_system {
 namespace drive_backend {
 
+class SyncEngineContext;
+
 class LocalToRemoteSyncer : public SyncTask {
  public:
-  LocalToRemoteSyncer();
+  explicit LocalToRemoteSyncer(SyncEngineContext* sync_context);
   virtual ~LocalToRemoteSyncer();
   virtual void Run(const SyncStatusCallback& callback) OVERRIDE;
 
  private:
+  SyncEngineContext* sync_context_;  // Not owned.
+
+  base::WeakPtrFactory<LocalToRemoteSyncer> weak_ptr_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(LocalToRemoteSyncer);
 };
 
 }  // namespace drive_backend
 }  // namespace sync_file_system
 
 #endif  // CHROME_BROWSER_SYNC_FILE_SYSTEM_DRIVE_BACKEND_LOCAL_TO_REMOTE_SYNCER_H_