chrome: Cleanup class/struct forward declarations

chrome/browser/chromeos/login/users/multi_profile_user_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 CHROME_BROWSER_CHROMEOS_LOGIN_USERS_MULTI_PROFILE_USER_CONTROLLER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_MULTI_PROFILE_USER_CONTROLLER_H_
 
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/scoped_vector.h"
 
 class PrefChangeRegistrar;
 class PrefRegistrySimple;
 class PrefService;
 class Profile;
 
 namespace user_prefs {
 class PrefRegistrySyncable;
 }
 
 namespace chromeos {
 
 class MultiProfileUserControllerDelegate;
-class UserManager;
 
 // MultiProfileUserController decides whether a user is allowed to be in a
 // multi-profiles session. It caches the multi-profile user behavior pref backed
 // by user policy into local state so that the value is available before the
 // user login and checks if the meaning of the value is respected.
 class MultiProfileUserController {
  public:
   // Second return value of IsUserAllowedInSession().
   enum UserAllowedInSessionReason {
     // User is allowed in multi-profile session.
@@ skipping 67 matching lines @@
   MultiProfileUserControllerDelegate* delegate_;  // Not owned.
   PrefService* local_state_;  // Not owned.
   ScopedVector<PrefChangeRegistrar> pref_watchers_;
 
   DISALLOW_COPY_AND_ASSIGN(MultiProfileUserController);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USERS_MULTI_PROFILE_USER_CONTROLLER_H_