[Sync] Refactor sync configuration logic.

chrome/browser/sync/glue/sync_backend_host.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_GLUE_SYNC_BACKEND_HOST_H_
 #define CHROME_BROWSER_SYNC_GLUE_SYNC_BACKEND_HOST_H_
 #pragma once
 
 #include <string>
 
@@ skipping 207 matching lines @@
   // |sync_disabled| indicates if syncing is being disabled or not.
   // See the implementation and Core::DoShutdown for details.
   // Must be called *after* StopSyncingForShutdown.
   void Shutdown(bool sync_disabled);
 
   // Changes the set of data types that are currently being synced.
   // The ready_task will be run when configuration is done with the
   // set of all types that failed configuration (i.e., if its argument
   // is non-empty, then an error was encountered).
   virtual void ConfigureDataTypes(
-      sync_api::ConfigureReason reason,
-      syncable::ModelTypeSet types_to_add,
-      syncable::ModelTypeSet types_to_remove,
+      const sync_api::ConfigureReason& reason,
+      const syncable::ModelTypeSet& desired_types,
+      const syncable::ModelTypeSet& disabled_types,
       NigoriState nigori_state,
-      base::Callback<void(syncable::ModelTypeSet)> ready_task,
-      base::Callback<void()> retry_callback) OVERRIDE;
-
-  // Makes an asynchronous call to syncer to switch to config mode. When done
-  // syncer will call us back on FinishConfigureDataTypes.
-  virtual void StartConfiguration(const base::Closure& callback);
+      const base::Callback<void(syncable::ModelTypeSet)>& ready_task,
+      const base::Callback<void()>& retry_callback) OVERRIDE;
 
   // Turns on encryption of all present and future sync data.
   virtual void EnableEncryptEverything();
 
   // Activates change processing for the given data type.  This must
   // be called synchronously with the data type's model association so
   // no changes are dropped between model association and change
   // processor activation.
   void ActivateDataType(
       syncable::ModelType type, ModelSafeGroup group,
@@ skipping 78 matching lines @@
     bool delete_sync_data_folder;
     std::string restored_key_for_bootstrapping;
     sync_api::SyncManager::TestingMode testing_mode;
     UnrecoverableErrorHandler* unrecoverable_error_handler;
     ReportUnrecoverableErrorFunction report_unrecoverable_error_function;
   };
 
   // Allows tests to perform alternate core initialization work.
   virtual void InitCore(const DoInitializeOptions& options);
 
-  // Called from Core::OnSyncCycleCompleted to handle updating frontend
-  // thread components.
-  void HandleSyncCycleCompletedOnFrontendLoop(
-      const sessions::SyncSessionSnapshot& snapshot);
+  // Request the syncer to reconfigure with the specfied params.
+  // Virtual for testing.
+  virtual void RequestConfigureSyncer(
+      sync_api::ConfigureReason reason,
+      syncable::ModelTypeSet types_to_config,
+      const browser_sync::ModelSafeRoutingInfo routing_info,
+      const base::Callback<void(syncable::ModelTypeSet)>& ready_task,
+      const base::Closure& retry_callback);
 
-  // Called to finish the job of ConfigureDataTypes once the syncer is in
-  // configuration mode.
-  void FinishConfigureDataTypesOnFrontendLoop();
-
-  bool IsDownloadingNigoriForTest() const;
+  // Called when the syncer has finished performing a configuration.
+  void FinishConfigureDataTypesOnFrontendLoop(
+    const syncable::ModelTypeSet& types_to_configure,
+    const syncable::ModelTypeSet& configured_types,
+    const base::Callback<void(syncable::ModelTypeSet)>& ready_task);
 
  private:
   // The real guts of SyncBackendHost, to keep the public client API clean.
   class Core;
 
   // An enum representing the steps to initializing the SyncBackendHost.
   enum InitializationState {
     NOT_ATTEMPTED,
     CREATING_SYNC_MANAGER,  // We're waiting for the first callback from the
                             // sync thread to inform us that the sync manager
                             // has been created.
     NOT_INITIALIZED,        // Initialization hasn't completed, but we've
                             // constructed a SyncManager.
     DOWNLOADING_NIGORI,     // The SyncManager is initialized, but
                             // we're fetching encryption information.
     REFRESHING_NIGORI,      // The SyncManager is initialized, and we
                             // have the encryption information, but we
                             // still need to refresh encryption. Also, we need
                             // to update the device information in the nigori.
     INITIALIZED,            // Initialization is complete.
   };
 
-  struct PendingConfigureDataTypesState {
-    PendingConfigureDataTypesState();
-    ~PendingConfigureDataTypesState();
-
-    // The ready_task will be run when configuration is done with the
-    // set of all types that failed configuration (i.e., if its
-    // argument is non-empty, then an error was encountered).
-    base::Callback<void(syncable::ModelTypeSet)> ready_task;
-
-    // The retry callback will be run when the download failed due to a
-    // transient error. This is to notify DTM so it can apropriately inform
-    // the UI. Note: The retry_callback will be run only once and after
-    // that we will not notify DTM until the sync is successful or in a
-    // permanent error state.
-    base::Callback<void()> retry_callback;
-
-    // The set of types that we are waiting to be initially synced in a
-    // configuration cycle.
-    syncable::ModelTypeSet types_to_add;
-
-    // Additional details about which types were added.
-    syncable::ModelTypeSet added_types;
-    sync_api::ConfigureReason reason;
-    bool retry_in_progress;
-  };
-
   // Checks if we have received a notice to turn on experimental datatypes
   // (via the nigori node) and informs the frontend if that is the case.
   // Note: it is illegal to call this before the backend is initialized.
   void AddExperimentalTypes();
 
   // Downloading of nigori failed and will be retried.
-  virtual void OnNigoriDownloadRetry();
+  void OnNigoriDownloadRetry();
 
   // InitializationComplete passes through the SyncBackendHost to forward
   // on to |frontend_|, and so that tests can intercept here if they need to
   // set up initial conditions.
-  virtual void HandleInitializationCompletedOnFrontendLoop(
+  void HandleInitializationCompletedOnFrontendLoop(
       const WeakHandle<JsBackend>& js_backend,
       bool success);
 
+  // Called from Core::OnSyncCycleCompleted to handle updating frontend
+  // thread components.
+  void HandleSyncCycleCompletedOnFrontendLoop(
+      const sessions::SyncSessionSnapshot& snapshot);
+
+  // Called when the syncer failed to perform a configuration and will
+  // eventually retry. FinishingConfigurationOnFrontendLoop(..) will be called
+  // on successful completion.
+  void RetryConfigurationOnFrontendLoop(
+      const base::Closure& retry_callback);
+
   // Helpers to persist a token that can be used to bootstrap sync encryption
   // across browser restart to avoid requiring the user to re-enter their
   // passphrase.  |token| must be valid UTF-8 as we use the PrefService for
   // storage.
   void PersistEncryptionBootstrapToken(const std::string& token);
 
   // For convenience, checks if initialization state is INITIALIZED.
   bool initialized() const { return initialization_state_ == INITIALIZED; }
 
   // Let the front end handle the actionable error event.
@@ skipping 83 matching lines @@
 
   sync_notifier::SyncNotifierFactory sync_notifier_factory_;
 
   ChromeExtensionsActivityMonitor extensions_activity_monitor_;
 
   scoped_ptr<SyncBackendRegistrar> registrar_;
 
   // The frontend which we serve (and are owned by).
   SyncFrontend* frontend_;
 
-  scoped_ptr<PendingConfigureDataTypesState> pending_download_state_;
-  scoped_ptr<PendingConfigureDataTypesState> pending_config_mode_state_;
-
   // We cache the cryptographer's pending keys whenever NotifyPassphraseRequired
   // is called. This way, before the UI calls SetDecryptionPassphrase on the
   // syncer, it can avoid the overhead of an asynchronous decryption call and
   // give the user immediate feedback about the passphrase entered by first
   // trying to decrypt the cached pending keys on the UI thread. Note that
   // SetDecryptionPassphrase can still fail after the cached pending keys are
   // successfully decrypted if the pending keys have changed since the time they
   // were cached.
   sync_pb::EncryptedData cached_pending_keys_;
 
   // UI-thread cache of the last SyncSessionSnapshot received from syncapi.
   sessions::SyncSessionSnapshot last_snapshot_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncBackendHost);
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_GLUE_SYNC_BACKEND_HOST_H_