[cros login] Split login related classes into subfolders.

chrome/browser/chromeos/login/user_adding_screen.h

-// Copyright 2013 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_USER_ADDING_SCREEN_H_
-#define CHROME_BROWSER_CHROMEOS_LOGIN_USER_ADDING_SCREEN_H_
-
-#include "base/basictypes.h"
-
-namespace chromeos {
-
-// An interface that defines screen for adding users into multi-profile session.
-// Current implementation is a singleton.
-// TODO(dzhioev): get rid of singleton.
-class UserAddingScreen {
- public:
-  struct Observer {
-    virtual void OnUserAddingStarted() {}
-    virtual void OnUserAddingFinished() {}
-    virtual ~Observer() {}
-  };
-
-  static UserAddingScreen* Get();
-
-  virtual void Start() = 0;
-  virtual void Cancel() = 0;
-  virtual bool IsRunning() = 0;
-
-  virtual void AddObserver(Observer* observer) = 0;
-  virtual void RemoveObserver(Observer* observer) = 0;
-
- protected:
-  UserAddingScreen();
-  virtual ~UserAddingScreen();
-
-  DISALLOW_COPY_AND_ASSIGN(UserAddingScreen);
-};
-
-}  // namespace chromeos
-
-#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USER_ADDING_SCREEN_H_
-