NTP4/Sync Promo:

chrome/browser/resources/ntp4/new_tab.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 New tab page
  * This is the main code for the new tab page used by touch-enabled Chrome
  * browsers.  For now this is still a prototype.
  */
 
@@ skipping 910 matching lines @@
    * Updates the text displayed in the login container. If there is no text then
    * the login container is hidden.
    * @param {string} loginHeader The first line of text.
    * @param {string} loginSubHeader The second line of text.
    */
   function updateLogin(loginHeader, loginSubHeader) {
     if (loginHeader || loginSubHeader) {
       $('login-container').hidden = false;
       $('login-status-header').innerHTML = loginHeader;
       $('login-status-sub-header').innerHTML = loginSubHeader;
+      $('card-slider-frame').classList.add('showing-login-area');
     } else {
       $('login-container').hidden = true;
+      $('card-slider-frame').classList.remove('showing-login-area');
     }
   }
 
   // Return an object with all the exports
   return {
     appAdded: appAdded,
     appRemoved: appRemoved,
     appsPrefChangeCallback: appsPrefChangeCallback,
     assert: assert,
     bookmarkImportBegan: bookmarkImportBegan,
@@ skipping 30 matching lines @@
 var getAppsCallback = ntp4.getAppsCallback;
 var appsPrefChangeCallback = ntp4.appsPrefChangeCallback;
 var themeChanged = ntp4.themeChanged;
 var recentlyClosedTabs = ntp4.setRecentlyClosedTabs;
 var setMostVisitedPages = ntp4.setMostVisitedPages;
 var updateLogin = ntp4.updateLogin;
 
 document.addEventListener('DOMContentLoaded', ntp4.initialize);
 window.addEventListener('online', ntp4.updateOfflineEnabledApps);
 window.addEventListener('offline', ntp4.updateOfflineEnabledApps);