mash: Migrate some system user files to common.

ash/system/user/user_card_view.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 ASH_SYSTEM_USER_USER_CARD_VIEW_H_
 #define ASH_SYSTEM_USER_USER_CARD_VIEW_H_
 
-#include "ash/system/user/login_status.h"
 #include "base/macros.h"
 #include "ui/views/view.h"
 
 namespace ash {
+
+enum class LoginStatus;
+
 namespace tray {
 
 // The view displaying information about the user, such as user's avatar, email
 // address, name, and more. View has no borders.
 class UserCardView : public views::View {
  public:
   // |max_width| takes effect only if |login_status| is LOGGED_IN_PUBLIC.
   UserCardView(LoginStatus login_status, int max_width, int user_index);
   ~UserCardView() override;
 
   // views::View overrides.
   void GetAccessibleState(ui::AXViewState* state) override;
 
  private:
   // Creates the content for the public mode.
   void AddPublicModeUserContent(int max_width);
 
   void AddUserContent(LoginStatus login_status, int user_index);
 
   // Create a user icon representation.
   views::View* CreateIcon(LoginStatus login_status, int user_index);
 
   DISALLOW_COPY_AND_ASSIGN(UserCardView);
 };
 
 }  // namespace tray
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_USER_USER_CARD_VIEW_H_