[SyncFS] Support late authentication

- Make observers to external services sticky over re-initialization.
- Leave SyncWorker NULL when non sign-in state.
- Observe sign-in event and trigger initialization on it.

BUG=374101,380615

Review URL: https://codereview.chromium.org/324343002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@276591 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/sync_file_system/drive_backend/sync_engine.h

@@ -18,11 +18,11 @@
 #include "chrome/browser/sync_file_system/remote_file_sync_service.h"
 #include "chrome/browser/sync_file_system/sync_action.h"
 #include "chrome/browser/sync_file_system/sync_direction.h"
+#include "components/signin/core/browser/signin_manager_base.h"
 #include "net/base/network_change_notifier.h"
 
 class ExtensionServiceInterface;
 class ProfileOAuth2TokenService;
-class SigninManagerBase;
 
 namespace base {
 class SequencedTaskRunner;
@@ -60,9 +60,10 @@ class SyncEngine : public RemoteFileSyncService,
                    public LocalChangeProcessor,
                    public drive::DriveNotificationObserver,
                    public drive::DriveServiceObserver,
-                   public net::NetworkChangeNotifier::NetworkChangeObserver {
+                   public net::NetworkChangeNotifier::NetworkChangeObserver,
+                   public SigninManagerBase::Observer {
  public:
-  typedef Observer SyncServiceObserver;
+  typedef RemoteFileSyncService::Observer SyncServiceObserver;
 
   static scoped_ptr<SyncEngine> CreateForBrowserContext(
       content::BrowserContext* context,
@@ -131,13 +132,11 @@ class SyncEngine : public RemoteFileSyncService,
   virtual void OnNetworkChanged(
       net::NetworkChangeNotifier::ConnectionType type) OVERRIDE;
 
-  void OnPendingFileListUpdated(int item_count);
-  void OnFileStatusChanged(const fileapi::FileSystemURL& url,
-                           SyncFileStatus file_status,
-                           SyncAction sync_action,
-                           SyncDirection direction);
-  void UpdateServiceState(RemoteServiceState state,
-                          const std::string& description);
+  // SigninManagerBase::Observer overrides.
+  virtual void GoogleSigninFailed(const GoogleServiceAuthError& error) OVERRIDE;
+  virtual void GoogleSigninSucceeded(const std::string& username,
+                                     const std::string& password) OVERRIDE;
+  virtual void GoogleSignedOut(const std::string& username) OVERRIDE;
 
  private:
   class WorkerObserver;
@@ -158,6 +157,15 @@ class SyncEngine : public RemoteFileSyncService,
              net::URLRequestContextGetter* request_context,
              leveldb::Env* env_override);
 
+  // Called by WorkerObserver.
+  void OnPendingFileListUpdated(int item_count);
+  void OnFileStatusChanged(const fileapi::FileSystemURL& url,
+                           SyncFileStatus file_status,
+                           SyncAction sync_action,
+                           SyncDirection direction);
+  void UpdateServiceState(RemoteServiceState state,
+                          const std::string& description);
+
   SyncStatusCallback TrackCallback(const SyncStatusCallback& callback);
 
   scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner_;

chrome/browser/sync_file_system/drive_backend/sync_worker.cc

@@ -337,7 +337,7 @@ void SyncWorker::OnNotificationReceived() {
   MaybeScheduleNextTask();
 }
 
-void SyncWorker::OnReadyToSendRequests(const std::string& account_id) {
+void SyncWorker::OnReadyToSendRequests() {
   DCHECK(sequence_checker_.CalledOnValidSequencedThread());
 
   has_refresh_token_ = true;
@@ -346,8 +346,7 @@ void SyncWorker::OnReadyToSendRequests(const std::string& account_id) {
     return;
   UpdateServiceState(REMOTE_SERVICE_OK, "Authenticated");
 
-  if (!GetMetadataDatabase() && !account_id.empty()) {
-    GetDriveService()->Initialize(account_id);
+  if (!GetMetadataDatabase()) {
     PostInitializeTask();
     return;
   }

chrome/browser/sync_file_system/drive_backend/sync_worker.h

@@ -125,7 +125,7 @@ class SyncWorker : public SyncWorkerInterface,
 
   virtual void OnNotificationReceived() OVERRIDE;
 
-  virtual void OnReadyToSendRequests(const std::string& account_id) OVERRIDE;
+  virtual void OnReadyToSendRequests() OVERRIDE;
   virtual void OnRefreshTokenInvalid() OVERRIDE;
 
   virtual void OnNetworkChanged(

chrome/browser/sync_file_system/drive_backend/sync_worker_interface.h

@@ -80,7 +80,7 @@ class SyncWorkerInterface {
   virtual void OnNotificationReceived() = 0;
 
   // See drive::DriveServiceObserver for the details.
-  virtual void OnReadyToSendRequests(const std::string& account_id) = 0;
+  virtual void OnReadyToSendRequests() = 0;
   virtual void OnRefreshTokenInvalid() = 0;
 
   // See net::NetworkChangeNotifier::NetworkChangeObserver for the details.

chrome/browser/sync_file_system/drive_backend/sync_worker_unittest.cc

@@ -15,7 +15,6 @@
 #include "chrome/browser/sync_file_system/drive_backend/sync_engine_context.h"
 #include "chrome/browser/sync_file_system/drive_backend/sync_task.h"
 #include "chrome/browser/sync_file_system/drive_backend/sync_task_manager.h"
-#include "chrome/browser/sync_file_system/drive_backend/sync_worker.h"
 #include "chrome/browser/sync_file_system/sync_file_system_test_util.h"
 #include "content/public/test/test_browser_thread_bundle.h"
 #include "extensions/common/extension.h"