[Sync] Start up immediately when entering the sync setup UI.

components/sync_driver/startup_controller.h

 // Copyright 2014 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 COMPONENTS_SYNC_DRIVER_STARTUP_CONTROLLER_H_
 #define COMPONENTS_SYNC_DRIVER_STARTUP_CONTROLLER_H_
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
@@ skipping 43 matching lines @@
   void OnDataTypeRequestsSyncStartup(syncer::ModelType type);
 
   // Prepares this object for a new attempt to start sync, forgetting
   // whether or not preconditions were previously met.
   // NOTE: This resets internal state managed by this class, but does not
   // touch values that are explicitly set and reset by higher layers to
   // tell this class whether a setup UI dialog is being shown to the user.
   // See setup_in_progress_.
   void Reset(const syncer::ModelTypeSet registered_types);
 
-  void set_setup_in_progress(bool in_progress);
+  // Sets the setup in progress flag and tries to start sync if it's true.
+  void SetSetupInProgress(bool setup_in_progress);
+
   bool IsSetupInProgress() const { return setup_in_progress_; }
   base::Time start_backend_time() const { return start_backend_time_; }
   std::string GetBackendInitializationStateString() const;
 
   void OverrideFallbackTimeoutForTest(const base::TimeDelta& timeout);
 
  private:
   enum StartUpDeferredOption {
     STARTUP_BACKEND_DEFERRED,
     STARTUP_IMMEDIATE
@@ skipping 11 matching lines @@
 
   // The time that StartUp() is called. This is used to calculate time spent
   // in the deferred state; that is, after StartUp and before invoking the
   // start_backend_ callback.
   base::Time start_up_time_;
 
   // If |true|, there is setup UI visible so we should not start downloading
   // data types.
   // Note: this is explicitly controlled by higher layers (UI) and is meant to
   // reflect what the UI claims the setup state to be. Therefore, only set this
-  // due to explicit requests to do so via set_setup_in_progress.
+  // due to explicit requests to do so via SetSetupInProgress.
   bool setup_in_progress_;
 
   const sync_driver::SyncPrefs* sync_prefs_;
 
   const ProfileOAuth2TokenService* token_service_;
 
   const SigninManagerWrapper* signin_;
 
   // The callback we invoke when it's time to call expensive
   // startup routines for the sync backend.
   base::Closure start_backend_;
 
   // The time at which we invoked the start_backend_ callback.
   base::Time start_backend_time_;
 
   base::TimeDelta fallback_timeout_;
 
   // Used to compute preferred_types from SyncPrefs as-needed.
   syncer::ModelTypeSet registered_types_;
 
   base::WeakPtrFactory<StartupController> weak_factory_;
 };
 
 }  // namespace browser_sync
 
 #endif  // COMPONENTS_SYNC_DRIVER_STARTUP_CONTROLLER_H_