Revert "Revert 142517 - [Sync] Refactor sync configuration logic."

chrome/browser/sync/glue/sync_backend_host.h

Index: chrome/browser/sync/glue/sync_backend_host.h
diff --git a/chrome/browser/sync/glue/sync_backend_host.h b/chrome/browser/sync/glue/sync_backend_host.h
index 02352f40117409cea0d6b3dde617b5b9dfa6771a..3de9a815e3107922dd621f994fd19dcc7155ef51 100644
--- a/chrome/browser/sync/glue/sync_backend_host.h
+++ b/chrome/browser/sync/glue/sync_backend_host.h
@@ -25,6 +25,7 @@
 #include "sync/internal_api/public/engine/model_safe_worker.h"
 #include "sync/internal_api/public/sessions/sync_session_snapshot.h"
 #include "sync/internal_api/public/sync_manager.h"
+#include "sync/internal_api/public/sync_manager_factory.h"
 #include "sync/internal_api/public/util/report_unrecoverable_error_function.h"
 #include "sync/internal_api/public/util/unrecoverable_error_handler.h"
 #include "sync/internal_api/public/util/weak_handle.h"
@@ -170,6 +171,7 @@ class SyncBackendHost : public BackendDataTypeConfigurer {
       syncer::ModelTypeSet initial_types,
       const syncer::SyncCredentials& credentials,
       bool delete_sync_data_folder,
+      syncer::SyncManagerFactory* sync_manager_factory,
       syncer::UnrecoverableErrorHandler* unrecoverable_error_handler,
       syncer::ReportUnrecoverableErrorFunction
           report_unrecoverable_error_function);
@@ -225,12 +227,8 @@ class SyncBackendHost : public BackendDataTypeConfigurer {
       syncer::ModelTypeSet types_to_add,
       syncer::ModelTypeSet types_to_remove,
       NigoriState nigori_state,
-      base::Callback<void(syncer::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(syncer::ModelTypeSet)>& ready_task,
+      const base::Callback<void()>& retry_callback) OVERRIDE;
 
   // Turns on encryption of all present and future sync data.
   virtual void EnableEncryptEverything();
@@ -280,7 +278,7 @@ class SyncBackendHost : public BackendDataTypeConfigurer {
   // TODO(akalin): Figure out a better way for tests to hook into
   // SyncBackendHost.
 
-  typedef base::Callback<syncer::HttpPostProviderFactory*(void)>
+  typedef base::Callback<scoped_ptr<syncer::HttpPostProviderFactory>(void)>
       MakeHttpBridgeFactoryFn;
 
   struct DoInitializeOptions {
@@ -296,6 +294,7 @@ class SyncBackendHost : public BackendDataTypeConfigurer {
         const syncer::SyncCredentials& credentials,
         ChromeSyncNotificationBridge* chrome_sync_notification_bridge,
         syncer::SyncNotifierFactory* sync_notifier_factory,
+        syncer::SyncManagerFactory* sync_manager_factory,
         bool delete_sync_data_folder,
         const std::string& restored_key_for_bootstrapping,
         syncer::SyncManager::TestingMode testing_mode,
@@ -316,6 +315,7 @@ class SyncBackendHost : public BackendDataTypeConfigurer {
     syncer::SyncCredentials credentials;
     ChromeSyncNotificationBridge* const chrome_sync_notification_bridge;
     syncer::SyncNotifierFactory* const sync_notifier_factory;
+    syncer::SyncManagerFactory* const sync_manager_factory;
     std::string lsid;
     bool delete_sync_data_folder;
     std::string restored_key_for_bootstrapping;
@@ -325,19 +325,31 @@ class SyncBackendHost : public BackendDataTypeConfigurer {
         report_unrecoverable_error_function;
   };
 
+  // Allow derived classes to start the sync thread early.
+  // Returns true on success, false otherwise. If the thread was already
+  // running, does nothing and returns true.
+  bool StartSyncThread();
+
+  // Getter for derived classes. May be NULL if the thread is not running.
+  MessageLoop* sync_loop() const { return sync_thread_.message_loop(); }
+
   // 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 syncer::sessions::SyncSessionSnapshot& snapshot);
-
-  // Called to finish the job of ConfigureDataTypes once the syncer is in
-  // configuration mode.
-  void FinishConfigureDataTypesOnFrontendLoop();
+  // Request the syncer to reconfigure with the specfied params.
+  // Virtual for testing.
+  virtual void RequestConfigureSyncer(
+      syncer::ConfigureReason reason,
+      syncer::ModelTypeSet types_to_config,
+      const syncer::ModelSafeRoutingInfo& routing_info,
+      const base::Callback<void(syncer::ModelTypeSet)>& ready_task,
+      const base::Closure& retry_callback);
 
-  bool IsDownloadingNigoriForTest() const;
+  // Called when the syncer has finished performing a configuration.
+  void FinishConfigureDataTypesOnFrontendLoop(
+      const syncer::ModelTypeSet types_to_configure,
+      const syncer::ModelTypeSet configured_types,
+      const base::Callback<void(syncer::ModelTypeSet)>& ready_task);
 
  private:
   // The real guts of SyncBackendHost, to keep the public client API clean.
@@ -351,6 +363,8 @@ class SyncBackendHost : public BackendDataTypeConfigurer {
                             // has been created.
     NOT_INITIALIZED,        // Initialization hasn't completed, but we've
                             // constructed a SyncManager.
+    CLEANING_NIGORI,        // A partially downloaded nigori was found. We
+                            // perform a configuration cycle to blow it away.
     DOWNLOADING_NIGORI,     // The SyncManager is initialized, but
                             // we're fetching encryption information.
     REFRESHING_NIGORI,      // The SyncManager is initialized, and we
@@ -360,31 +374,12 @@ class SyncBackendHost : public BackendDataTypeConfigurer {
     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(syncer::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.
-    syncer::ModelTypeSet types_to_add;
-
-    // Additional details about which types were added.
-    syncer::ModelTypeSet added_types;
-    syncer::ConfigureReason reason;
-    bool retry_in_progress;
-  };
+  // 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.
+  void HandleInitializationCompletedOnFrontendLoop(
+      const syncer::WeakHandle<syncer::JsBackend>& js_backend,
+      bool success);
 
   // 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.
@@ -392,14 +387,17 @@ class SyncBackendHost : public BackendDataTypeConfigurer {
   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(
-      const syncer::WeakHandle<syncer::JsBackend>& js_backend,
-      bool success);
+  // Called from Core::OnSyncCycleCompleted to handle updating frontend
+  // thread components.
+  void HandleSyncCycleCompletedOnFrontendLoop(
+      const syncer::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
@@ -500,9 +498,6 @@ class SyncBackendHost : public BackendDataTypeConfigurer {
   // 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