Add RemoteFileSyncService interface

chrome/browser/sync_file_system/remote_file_sync_service.h

Index: chrome/browser/sync_file_system/remote_file_sync_service.h
diff --git a/chrome/browser/sync_file_system/remote_file_sync_service.h b/chrome/browser/sync_file_system/remote_file_sync_service.h
new file mode 100644
index 0000000000000000000000000000000000000000..bcd93d717dcdcdefdb223b75cbbfdf68bca360cf
--- /dev/null
+++ b/chrome/browser/sync_file_system/remote_file_sync_service.h
@@ -0,0 +1,46 @@
+// 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_REMOTE_FILE_SYNC_SERVICE_H_
+#define CHROME_BROWSER_SYNC_FILE_SYSTEM_REMOTE_FILE_SYNC_SERVICE_H_
+
+#include "base/basictypes.h"
+#include "webkit/fileapi/syncable/sync_callbacks.h"
+
+class GURL;
+
+namespace sync_file_system {
+
+class RemoteChangeObserver;
+class RemoteChangeProcessor;
+
+// This class represents a backing service of the sync filesystem.
+// Owned by SyncFileSystemService.
+class RemoteFileSyncService {
+ public:
+  RemoteFileSyncService() {}
+  virtual ~RemoteFileSyncService() {}
+
+  virtual void AddObserver(RemoteChangeObserver* observer) = 0;
+  virtual void RemoveObserver(RemoteChangeObserver* observer) = 0;
+
+  // Registers |origin| to track remote side changes for the |origin|.
+  virtual void RegisterOriginForTrackingChanges(const GURL& origin) = 0;
+
+  // Unregisters |origin| to track remote side changes for the |origin|.
+  virtual void UnregisterOriginForTrackingChanges(const GURL& origin) = 0;
+
+  // Called by the sync engine to process one remote change.
+  // After a change is processed |callback| will be called (to return
+  // the control to the sync engine).
+  virtual void ProcessChange(RemoteChangeProcessor* processor,
+                             fileapi::SyncCompletionCallback& callback) = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(RemoteFileSyncService);
+};
+
+}  // namespace sync_file_system
+
+#endif  // CHROME_BROWSER_SYNC_FILE_SYSTEM_REMOTE_FILE_SYNC_SERVICE_H_