Reset username for the Active Directory login

chrome/browser/resources/chromeos/login/screen_gaia_signin.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 Oobe signin screen implementation.
  */
 
 login.createScreen('GaiaSigninScreen', 'gaia-signin', function() {
   // GAIA animation guard timer. Started when GAIA page is loaded
@@ skipping 1073 matching lines @@
     },
 
     loadAdAuth: function(params) {
       this.loading = true;
       this.startLoadingTimer_();
       var ADAuthUI = this.getSigninFrame_();
       if ('realm' in params) {
         ADAuthUI.realm = params['realm'];
         ADAuthUI.userRealm = '@' + params['realm'];
       }
-      if ('email' in params)

[achuithb, 2017/01/30 23:53:34]

How does this change help?

-        ADAuthUI.setUser(params['email']);
+      ADAuthUI.setUser(params['email']);
       this.onAuthReady_();
     },
 
     /**
      * Show/Hide error when user is not in whitelist. When UI is hidden
      * GAIA is reloaded.
      * @param {boolean} show Show/hide error UI.
      * @param {!Object} opt_data Optional additional information.
      */
     showWhitelistCheckFailedError: function(show, opt_data) {
@@ skipping 18 matching lines @@
     invalidateAd: function(username) {
       if (this.screenMode_ != ScreenMode.AD_AUTH)
         return;
       var adAuthUI = this.getSigninFrame_();
       adAuthUI.setUser(username);
       adAuthUI.setInvalid(ACTIVE_DIRECTORY_ERROR_STATE.BAD_PASSWORD);
       this.loading = false;
     }
   };
 });