Fix clicks on Public Session login page after OOBE

ui/login/account_picker/user_pod_row.js

 // Copyright 2014 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 User pod row implementation.
  */
 
 cr.define('login', function() {
   /**
@@ skipping 753 matching lines @@
       this.imageElement.addEventListener('load',
           this.parentNode.handlePodImageLoad.bind(this.parentNode, this));
 
       var initialAuthType = this.user.initialAuthType ||
           AUTH_TYPE.OFFLINE_PASSWORD;
       this.setAuthType(initialAuthType, null);
 
       this.userClickAuthAllowed_ = false;
 
       // Lazy load the assets needed for the polymer submit button.
-      if (cr.isChromeOS && !cr.ui.login.ResourceLoader.alreadyLoadedAssets(
+      if (cr.isChromeOS && this.submitButton &&
+          !cr.ui.login.ResourceLoader.alreadyLoadedAssets(

[Greg Levin, 2016/09/22 20:31:39]

I assume this condition makes sense, and that this code block is unneeded if
we're not displaying the Submit button...?

[jdufault, 2016/09/22 20:52:20]

Discussed a bit offline. We should probably just add a check to only load the
resource if the display type[1] is set to LOCK.

1: https://cs.chromium.org/chromium/src/ui/login/display_manager.js?l=84

               'custom-elements-user-pod')) {
         cr.ui.login.ResourceLoader.registerAssets({
             id: 'custom-elements-user-pod',
             html: [{ url: 'custom_elements_user_pod.html' }]
          });
         cr.ui.login.ResourceLoader.loadAssetsOnIdle('custom-elements-user-pod');

[Greg Levin, 2016/09/22 20:31:39]

After OOBE completed and the Public Session user pod came up, this block of code
was causing the bug, and particularly the weirdness described in Comment #13:
https://bugs.chromium.org/p/chromium/issues/detail?id=647082#c13

What exactly is this code for, anyway?  I ran the normal login page with it
commented out, and the Submit button arrows appeared and worked normally.

       }
     },
 
     /**
      * Resets tab order for pod elements to its initial state.
      */
     resetTabOrder: function() {
       // Note: the |mainInput| can be the pod itself.
       this.mainInput.tabIndex = -1;
       this.tabIndex = UserPodTabOrder.POD_INPUT;
@@ skipping 97 matching lines @@
      */
     get passwordElement() {
       return this.querySelector('.password');
     },
 
     /**
      * Gets submit button.
      * @type {!HTMLInputElement}
      */
     get submitButton() {
-      return this.querySelector('.submit-button');
+      return this.user_.publicAccount ? null :
+                                        this.querySelector('.submit-button');

[Greg Levin, 2016/09/22 20:31:39]

Public Session pods don't have Submit buttons.  Is it okay to skip all the "if
(this.submitButton)" code in that case?

     },
 
     /**
      * Gets the password label, which is used to show a message where the
      * password field is normally.
      * @type {!HTMLInputElement}
      */
     get passwordLabelElement() {
       return this.querySelector('.password-label');
     },
@@ skipping 2741 matching lines @@
        if (pod && pod.multiProfilesPolicyApplied) {
          pod.userTypeBubbleElement.classList.remove('bubble-shown');
        }
      }
   };
 
   return {
     PodRow: PodRow
   };
 });