Make sure OneClickSigninSyncStarter detects Browser object being closed

chrome/browser/ui/sync/one_click_signin_sync_starter.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_UI_SYNC_ONE_CLICK_SIGNIN_SYNC_STARTER_H_
 #define CHROME_BROWSER_UI_SYNC_ONE_CLICK_SIGNIN_SYNC_STARTER_H_
 
 #include <string>
 
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/signin/signin_tracker.h"
+#include "chrome/browser/ui/browser_list_observer.h"
 #include "chrome/browser/ui/host_desktop.h"
 
 class Browser;
 class ProfileSyncService;
 
 namespace policy {
 class CloudPolicyClient;
 }
 
 // Waits for successful singin notification from the signin manager and then
 // starts the sync machine.  Instances of this class delete themselves once
 // the job is done.
-class OneClickSigninSyncStarter : public SigninTracker::Observer {
+class OneClickSigninSyncStarter : public SigninTracker::Observer,
+                                  public chrome::BrowserListObserver {
  public:
   enum StartSyncMode {
     // Starts the process of signing the user in with the SigninManager, and
     // once completed automatically starts sync with all data types enabled.
     SYNC_WITH_DEFAULT_SETTINGS,
 
     // Starts the process of signing the user in with the SigninManager, and
     // once completed redirects the user to the settings page to allow them
     // to configure which data types to sync before sync is enabled.
     CONFIGURE_SYNC_FIRST,
@@ skipping 21 matching lines @@
   // signin before signin completes.
   OneClickSigninSyncStarter(Profile* profile,
                             Browser* browser,
                             const std::string& session_index,
                             const std::string& email,
                             const std::string& password,
                             StartSyncMode start_mode,
                             bool force_same_tab_navigation,
                             ConfirmationRequired display_confirmation);
 
+  // chrome::BrowserListObserver override.
+  virtual void OnBrowserRemoved(Browser* browser) OVERRIDE;
+
  private:
   virtual ~OneClickSigninSyncStarter();
 
   // Initializes the internals of the OneClickSigninSyncStarter object. Can also
   // be used to re-initialize the object to refer to a newly created profile.
   void Initialize(Profile* profile, Browser* browser);
 
   // SigninTracker::Observer override.
   virtual void GaiaCredentialsValid() OVERRIDE;
   virtual void SigninFailed(const GoogleServiceAuthError& error) OVERRIDE;
@@ skipping 75 matching lines @@
   // CloudPolicyClient reference we keep while determining whether to create
   // a new profile for an enterprise user or not.
   scoped_ptr<policy::CloudPolicyClient> policy_client_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(OneClickSigninSyncStarter);
 };
 
 
 #endif  // CHROME_BROWSER_UI_SYNC_ONE_CLICK_SIGNIN_SYNC_STARTER_H_