Update the Drive state in Files app when the refresh token is fetched.

chrome/browser/chromeos/extensions/file_manager/event_router.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_CHROMEOS_EXTENSIONS_FILE_MANAGER_EVENT_ROUTER_H_
 #define CHROME_BROWSER_CHROMEOS_EXTENSIONS_FILE_MANAGER_EVENT_ROUTER_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 103 matching lines @@
   void DefaultNetworkChanged(const chromeos::NetworkState* network) override;
 
   // drive::JobListObserver overrides.
   void OnJobAdded(const drive::JobInfo& job_info) override;
   void OnJobUpdated(const drive::JobInfo& job_info) override;
   void OnJobDone(const drive::JobInfo& job_info,
                  drive::FileError error) override;
 
   // drive::DriveServiceObserver overrides.
   void OnRefreshTokenInvalid() override;
+  void OnReadyToSendRequests() override;
 
   // drive::FileSystemObserver overrides.
   void OnDirectoryChanged(const base::FilePath& drive_path) override;
   void OnFileChanged(const drive::FileChange& changed_files) override;
   void OnDriveSyncError(drive::file_system::DriveSyncErrorType type,
                         const base::FilePath& drive_path) override;
 
   // VolumeManagerObserver overrides.
   void OnDiskAdded(const chromeos::disks::DiskMountManager::Disk& disk,
                    bool mounting) override;
@@ skipping 111 matching lines @@
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate the weak pointers before any other members are destroyed.
   base::WeakPtrFactory<EventRouter> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(EventRouter);
 };
 
 }  // namespace file_manager
 
 #endif  // CHROME_BROWSER_CHROMEOS_EXTENSIONS_FILE_MANAGER_EVENT_ROUTER_H_