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

chrome/browser/sync_file_system/sync_file_system_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_SYNC_FILE_SYSTEM_SERVICE_H_
 #define CHROME_BROWSER_SYNC_FILE_SYSTEM_SYNC_FILE_SYSTEM_SERVICE_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/callback_forward.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
 #include "chrome/browser/profiles/profile_keyed_service.h"
 #include "chrome/browser/profiles/profile_keyed_service_factory.h"
+#include "chrome/browser/sync_file_system/change_observer_interface.h"
 #include "webkit/fileapi/syncable/sync_status_code.h"
 
 class GURL;
 
 namespace fileapi {
 class FileSystemContext;
 }
 
 namespace sync_file_system {
 
 class LocalFileSyncService;
+class LocalChangeObserver;
+class RemoteChangeObserver;
 
-class SyncFileSystemService : public ProfileKeyedService {
+class SyncFileSystemService
+    : public ProfileKeyedService,
+      public LocalChangeObserver,
+      public RemoteChangeObserver {
  public:
   typedef base::Callback<void(fileapi::SyncStatusCode status)> StatusCallback;
 
   // ProfileKeyedService overrides.
   virtual void Shutdown() OVERRIDE;
 
   void InitializeForApp(
       fileapi::FileSystemContext* file_system_context,
       const std::string& service_name,
       const GURL& app_url,
       const StatusCallback& callback);
 
  private:
   friend class SyncFileSystemServiceFactory;
 
   explicit SyncFileSystemService(Profile* profile);
   virtual ~SyncFileSystemService();
 
   void Initialize(scoped_ptr<LocalFileSyncService> local_file_service);
 
+  // RemoteChangeObserver overrides.
+  virtual void OnLocalChangeAvailable(int64 pending_changes) OVERRIDE;
+
+  // LocalChangeObserver overrides.
+  virtual void OnRemoteChangeAvailable(int64 pending_changes) OVERRIDE;
+
   Profile* profile_;
 
+  int64 pending_local_changes_;
+  int64 pending_remote_changes_;
+
   scoped_ptr<LocalFileSyncService> local_file_service_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncFileSystemService);
 };
 
 class SyncFileSystemServiceFactory : public ProfileKeyedServiceFactory {
  public:
   static SyncFileSystemService* GetForProfile(Profile* profile);
   static SyncFileSystemService* FindForProfile(Profile* profile);
   static SyncFileSystemServiceFactory* GetInstance();
 
  private:
   friend struct DefaultSingletonTraits<SyncFileSystemServiceFactory>;
   SyncFileSystemServiceFactory();
   virtual ~SyncFileSystemServiceFactory();
 
   // ProfileKeyedServiceFactory overrides.
   virtual ProfileKeyedService* BuildServiceInstanceFor(
       Profile* profile) const OVERRIDE;
 };
 
 }  // namespace sync_file_system
 
 #endif  // CHROME_BROWSER_SYNC_FILE_SYSTEM_SYNC_FILE_SYSTEM_SERVICE_H_