drive: Fix a bug that broke "Delta Update Status" in chrome:drive-internals

chrome/browser/resources/chromeos/drive_internals.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.
 
 /**
  * Updates the Drive related Flags section.
  * @param {Array} flags List of dictionaries describing flags.
  */
 function updateDriveRelatedFlags(flags) {
   var ul = $('drive-related-flags');
@@ skipping 171 matching lines @@
       (localMetadata['account-metadata-refreshing'] ? ' (refreshing)' : '');
 }
 
 /**
  * Updates the summary about delta update status.
  * @param {Object} deltaUpdateStatus Dictionary describing delta update status.
  */
 function updateDeltaUpdateStatus(deltaUpdateStatus) {
   $('push-notification-enabled').textContent =
         deltaUpdateStatus['push-notification-enabled'];
-  $('polling-interval-sec').textContent =
-        deltaUpdateStatus['polling-interval-sec'];
   $('last-update-check-time').textContent =
         deltaUpdateStatus['last-update-check-time'];
   $('last-update-check-error').textContent =
         deltaUpdateStatus['last-update-check-error'];
 }
 
 /**
  * Updates the event log section.
  * @param {Array} log Array of events.
  */
@@ skipping 57 matching lines @@
   $('button-show-file-entries').addEventListener('click', function() {
     var button = $('button-show-file-entries');
     button.parentNode.removeChild(button);
     chrome.send('listFileEntries');
   });
 
   window.setInterval(function() {
     chrome.send('periodicUpdate');
   }, 1000);
 });