[cros] Display emails of users are stored in a separate dictionary in Local State.

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

 // Copyright (c) 2011 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 Account picker screen implementation.
  */
 
 cr.define('login', function() {
   /**
@@ skipping 65 matching lines @@
    * @param {array} users Array of user.
    * @param {boolean} animated Whether to use init animation.
    * @public
    */
   AccountPickerScreen.loadUsers = function(users, animated) {
     $('pod-row').loadPods(users, animated);
   };
 
   /**
    * Updates current image of a user.
-   * @param {string} email Email of the user for which to update the image.
+   * @param {string} username User for which to update the image.
    * @public
    */
-  AccountPickerScreen.updateUserImage = function(email) {
-    $('pod-row').updateUserImage(email);
+  AccountPickerScreen.updateUserImage = function(username) {
+    $('pod-row').updateUserImage(username);
   };
 
   /**
    * Updates Caps Lock state (for Caps Lock hint in password input field).
    * @param {boolean} enabled Whether Caps Lock is on.
    * @public
    */
   AccountPickerScreen.setCapsLockState = function(enabled) {
     $('pod-row').classList[enabled ? 'add' : 'remove']('capslock-on');
   };
 
   return {
     AccountPickerScreen: AccountPickerScreen
   };
 });