Add skeleton code to wire Local- and Remote- file sync services

chrome/browser/sync_file_system/local_file_sync_service.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 CHROME_BROWSER_SYNC_FILE_SYSTEM_LOCAL_FILE_SYNC_SERVICE_H_
 #define CHROME_BROWSER_SYNC_FILE_SYSTEM_LOCAL_FILE_SYNC_SERVICE_H_
 
 #include "base/basictypes.h"
 #include "base/callback_forward.h"
 #include "base/memory/ref_counted.h"
+#include "chrome/browser/sync_file_system/remote_change_processor.h"
 #include "webkit/fileapi/syncable/sync_status_code.h"
 
 class GURL;
 
 namespace fileapi {
 class FileSystemContext;
 class LocalFileSyncContext;
 }
 
 namespace sync_file_system {
 
+class LocalChangeProcessor;
+
 // Maintains local file change tracker and sync status.
 // Owned by SyncFileSystemService (which is a per-profile object).
-class LocalFileSyncService {
+class LocalFileSyncService : public RemoteChangeProcessor {
  public:
   typedef base::Callback<void(fileapi::SyncStatusCode)> StatusCallback;
 
   LocalFileSyncService();
   ~LocalFileSyncService();
 
   void Shutdown();
 
   void MaybeInitializeFileSystemContext(
       const GURL& app_url,
       fileapi::FileSystemContext* file_system_context,
       const StatusCallback& callback);
 
+  // Synchronize one local change (to the remote server) using |processor|.
+  // |processor| must have same or longer lifetime than this service.
+  void ProcessChange(LocalChangeProcessor* processor,
+                     const StatusCallback& callback);
+
+  // RemoteChangeProcessor overrides.
+  virtual void PrepareForProcessRemoteChange(
+      const fileapi::FileSystemURL& url,
+      const PrepareChangeCallback& callback) OVERRIDE;
+  virtual void ApplyRemoteChange(
+      const fileapi::FileChange& change,
+      const FilePath& local_path,
+      const fileapi::FileSystemURL& url,
+      const StatusCallback& callback) OVERRIDE;
+
  private:
   scoped_refptr<fileapi::LocalFileSyncContext> sync_context_;
 
   DISALLOW_COPY_AND_ASSIGN(LocalFileSyncService);
 };
 
 }  // namespace sync_file_system
 
 #endif  // CHROME_BROWSER_SYNC_FILE_SYSTEM_LOCAL_FILE_SYNC_SERVICE_H_