SyncFS v2: Add re-initialization code for temporary service failure case

chrome/browser/sync_file_system/drive_backend/sync_engine.cc

Index: chrome/browser/sync_file_system/drive_backend/sync_engine.cc
diff --git a/chrome/browser/sync_file_system/drive_backend/sync_engine.cc b/chrome/browser/sync_file_system/drive_backend/sync_engine.cc
index 6e7822f93d9081209702b12e6379c1d6230f57b8..81bb8ab0270c714ac35e63246d127c966d27fa04 100644
--- a/chrome/browser/sync_file_system/drive_backend/sync_engine.cc
+++ b/chrome/browser/sync_file_system/drive_backend/sync_engine.cc
@@ -148,6 +148,9 @@ void SyncEngine::AddFileStatusObserver(FileStatusObserver* observer) {
 void SyncEngine::RegisterOrigin(
     const GURL& origin,
     const SyncStatusCallback& callback) {
+  if (!metadata_database_ && drive_service_->HasRefreshToken())
+    PostInitializeTask();
+
   task_manager_->ScheduleSyncTaskAtPriority(
       scoped_ptr<SyncTask>(new RegisterAppTask(this, origin.host())),
       SyncTaskManager::PRIORITY_HIGH,
@@ -330,6 +333,9 @@ void SyncEngine::NotifyLastOperationStatus(
 }
 
 void SyncEngine::OnNotificationReceived() {
+  if (service_state_ == REMOTE_SERVICE_TEMPORARY_UNAVAILABLE)
+    UpdateServiceState(REMOTE_SERVICE_OK, "Got push notification for Drive.");
+
   should_check_remote_change_ = true;
   MaybeScheduleNextTask();
 }
@@ -437,8 +443,9 @@ void SyncEngine::PostInitializeTask() {
                                 task_runner_.get(),
                                 drive_service_.get(),
                                 base_dir_.Append(kDatabaseName));
-  task_manager_->ScheduleSyncTask(
+  task_manager_->ScheduleSyncTaskAtPriority(
       scoped_ptr<SyncTask>(initializer),
+      SyncTaskManager::PRIORITY_HIGH,
       base::Bind(&SyncEngine::DidInitialize, weak_ptr_factory_.GetWeakPtr(),
                  initializer));
 }