cros: Fold UserBoardModel into UserSelectionScreen.

chrome/browser/chromeos/login/ui/models/user_board_model.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_UI_MODELS_USER_BOARD_MODEL_H_
-#define CHROME_BROWSER_CHROMEOS_LOGIN_UI_MODELS_USER_BOARD_MODEL_H_
-
-#include "chrome/browser/chromeos/login/screens/base_screen.h"
-
-class AccountId;
-
-namespace chromeos {
-
-class UserBoardModel : public BaseScreen {
- public:
-  UserBoardModel();
-  ~UserBoardModel() override;
-
-  // Build list of users and send it to the webui.
-  virtual void SendUserList() = 0;
-
-  // Methods for easy unlock support.
-  virtual void HardLockPod(const AccountId& account_id) = 0;
-  virtual void AttemptEasyUnlock(const AccountId& account_id) = 0;
-  virtual void RecordClickOnLockIcon(const AccountId& account_id) = 0;
-
-  // Temorary unused methods:
-  void Show() override{};
-  void Hide() override{};
-};
-
-}  // namespace chromeos
-
-#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_UI_MODELS_USER_BOARD_MODEL_H_