Place sign out button on ash tray bubble in lockscreen state.

ash/system/user/tray_user.cc

 // 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.
 
 #include "ash/system/user/tray_user.h"
 
 #include <algorithm>
 #include <climits>
 #include <vector>
 
@@ skipping 743 matching lines @@
   } else if (add_menu_option_.get() &&
              sender == add_menu_option_->GetContentsView()) {
     // Let the user add another account to the session.
     ash::Shell::GetInstance()->system_tray_delegate()->ShowUserLogin();
   } else {
     NOTREACHED();
   }
 }
 
 void UserView::AddLogoutButton(ash::user::LoginStatus login) {
-  // A user should not be able to modify logged-in state when screen is
-  // locked.
-  if (login == ash::user::LOGGED_IN_LOCKED)
-    return;
-
   const base::string16 title = ash::user::GetLocalizedSignOutStringForStatus(
       login, true);
   TrayPopupLabelButton* logout_button = new TrayPopupLabelButton(this, title);
   logout_button->SetAccessibleName(title);
   logout_button_ = logout_button;
   // In public account mode, the logout button border has a custom color.
   if (login == ash::user::LOGGED_IN_PUBLIC) {
     TrayPopupLabelButtonBorder* border =
         static_cast<TrayPopupLabelButtonBorder*>(logout_button_->border());
     border->SetPainter(false, views::Button::STATE_NORMAL,
@@ skipping 508 matching lines @@
       kUserIconLargeSize : kUserIconSize;
 
   avatar_->SetImage(
       ash::Shell::GetInstance()->session_state_delegate()->GetUserImage(
           multiprofile_index_),
       gfx::Size(icon_size, icon_size));
 }
 
 }  // namespace internal
 }  // namespace ash