EnsureSyncRootDirectory 1453 chrome/browser/sync_file_system/drive_backend_v1/drive_file_sync_service.cc EnsureSyncRootDirectory(base::Bind( EnsureSyncRootDirectory 327 chrome/browser/sync_file_system/drive_backend_v1/drive_file_sync_service.h void EnsureSyncRootDirectory(const ResourceIdCallback& callback);