ChromeOS Gaia: Polishing Offline UI and Password changed UI according to specs

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

 /* Copyright 2015 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.
  */
 
 Polymer('offline-gaia', (function() {
   return {
     onTransitionEnd: function() {
       this.focus();
     },
@@ skipping 57 matching lines @@
       }
     },
 
     onBack: function() {
       this.switchToEmailCard();
     },
 
     switchToEmailCard() {
       this.$.passwordInput.inputValue = '';
       this.$.passwordInput.setValid(true);
+      this.$.emailInput.setValid(true);
       this.$.backButton.hidden = true;
       this.$.animatedPages.selected = 0;
     },
 
     switchToPasswordCard(email) {
       this.$.emailInput.inputValue = email;
       this.$.passwordHeader.email = email;
       this.$.backButton.hidden = false;
       this.$.animatedPages.selected = 1;
     }
   };
 })());