Prevented false error messages from user manager UI.

chrome/browser/resources/user_manager/control_bar.js

 // 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.
 
 /**
  * @fileoverview Desktop User Chooser UI control bar implementation.
  */
 
 cr.define('login', function() {
   /**
    * Creates a header bar element.
    * @constructor
    * @extends {HTMLDivElement}
    */
   var HeaderBar = cr.ui.define('div');
 
   HeaderBar.prototype = {
     __proto__: HTMLDivElement.prototype,
 
     // Whether guest button should be shown when header bar is in normal mode.
     showGuest_: true,
 
     // Current UI state of the sign-in screen.
-    signinUIState_: SIGNIN_UI_STATE.ACCOUNT_PICKER,
+    signinUIState_: SIGNIN_UI_STATE.HIDDEN,
 
     // Whether to show kiosk apps menu.
     hasApps_: false,
 
     /** @override */
     decorate: function() {
       $('add-user-button').addEventListener('click',
           this.handleAddUserClick_);
       $('cancel-add-user-button').addEventListener('click',
           this.handleCancelAddUserClick_);
@@ skipping 75 matching lines @@
     /**
      * Update current header bar UI.
      * @type {number} state Current state of the sign-in screen
      *                      (see SIGNIN_UI_STATE).
      */
     set signinUIState(state) {
       this.signinUIState_ = state;
       this.updateUI_();
     },
 
+    get signinUIState() {
+      return this.signinUIState_;
+    },
+
     /**
      * Whether the Cancel button is enabled during Gaia sign-in.
      * @type {boolean}
      */
     set allowCancel(value) {
       this.allowCancel_ = value;
       this.updateUI_();
     },
 
     /**
@@ skipping 38 matching lines @@
    */
   HeaderBar.animateOut = function(callback) {
     $('login-header-bar').animateOut(callback);
   };
 
   /**
    * Convenience wrapper of animateIn.
    */
   HeaderBar.animateIn = function() {
     $('login-header-bar').animateIn();
-  }
+  };
 
   return {
     HeaderBar: HeaderBar
   };
 });