Added login screen mode for adding users into session.

chrome/browser/resources/chromeos/login/header_bar.js

 // 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.
 
 /**
  * @fileoverview Login UI header bar implementation.
  */
 
 cr.define('login', function() {
   /**
@@ skipping 24 matching lines @@
       $('add-user-button').addEventListener('click',
           this.handleAddUserClick_);
       $('cancel-add-user-button').addEventListener('click',
           this.handleCancelAddUserClick_);
       $('guest-user-header-bar-item').addEventListener('click',
           this.handleGuestClick_);
       $('guest-user-button').addEventListener('click',
           this.handleGuestClick_);
       $('sign-out-user-button').addEventListener('click',
           this.handleSignoutClick_);
+      $('cancel-multiple-sign-in-button').addEventListener('click',
+          this.handleCancelMultipleSignInClick_);
 
       if (loadTimeData.getBoolean('enableAppMode') &&
-          loadTimeData.getString('screenType') == 'login') {
+          document.documentElement.getAttribute('screen') == 'login') {
         login.AppsMenuButton.decorate($('show-apps-button'));
       }
     },
 
     /**
      * Tab index value for all button elements.
      * @type {number}
      */
     set buttonsTabIndex(tabIndex) {
       var buttons = this.getElementsByTagName('button');
@@ skipping 66 matching lines @@
     /**
      * Shutdown button click handler.
      * @private
      */
     handleShutdownClick_: function(e) {
       chrome.send('shutdownSystem');
       e.stopPropagation();
     },
 
     /**
+     * Cancel user adding button handler.
+     * @private
+     */
+    handleCancelMultipleSignInClick_: function(e) {
+      chrome.send('cancelUserAdding');
+      e.stopPropagation();
+    },
+
+    /**
      * If true then "Browse as Guest" button is shown.
      * @type {boolean}
      */
     set showGuestButton(value) {
       this.showGuest_ = value;
       this.updateUI_();
     },
 
     /**
      * Update current header bar UI.
@@ skipping 44 matching lines @@
           isMultiProfilesUI;
       $('guest-user-header-bar-item').hidden = gaiaIsActive ||
           managedUserCreationDialogIsActive ||
           !this.showGuest_ ||
           wrongHWIDWarningIsActive ||
           isMultiProfilesUI;
       $('add-user-header-bar-item').hidden =
           $('add-user-button').hidden && $('cancel-add-user-button').hidden;
       $('apps-header-bar-item').hidden = !this.hasApps_ ||
           (!gaiaIsActive && !accountPickerIsActive);
+      $('cancel-multiple-sign-in-item').hidden = !isMultiProfilesUI;
 
       if (!$('apps-header-bar-item').hidden)
         $('show-apps-button').didShow();
     },
 
     /**
      * Animates Header bar to hide from the screen.
      * @param {function()} callback will be called once animation is finished.
      */
     animateOut: function(callback) {
@@ skipping 29 matching lines @@
    * Convenience wrapper of animateIn.
    */
   HeaderBar.animateIn = function() {
     $('login-header-bar').animateIn();
   }
 
   return {
     HeaderBar: HeaderBar
   };
 });