[Contextual Search] Update promo look.

chrome/browser/resources/contextual_search/promo.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.
 */
 
 <include src="../../../../ui/webui/resources/js/util.js">
 <include src="../../../../ui/webui/resources/js/load_time_data.js">
 
 /**
  * The amount of delay to use in the opt-in action in order to give time for
  * the fade-out animation to execute, before navigating to the opt-in URL,
  * in milliseconds.
  * @const
  */
 var OPT_IN_DELAY_MS = 65;
 
 /**
  * Once the DOM is loaded, determine if the header image is to be kept and
  * register a handler to add the 'hide' class to the container element in order
  * to hide it.
  */
 document.addEventListener('DOMContentLoaded', function(event) {
   if (config['hideHeader']) {
-    $('container').removeChild($('header-image'));
+    removeHeaderImages();
   }
   $('optin-button').addEventListener('click', function() {
     $('container').classList.add('hide');
     setTimeout(function() {
       location.hash = 'optin';
     }, OPT_IN_DELAY_MS);
   });
   $('optout-button').addEventListener('click', function() {
     location.hash = 'optout';
   });
 });
 
 /**
  * Returns the height of the content. Method called from Chrome to properly size
  * the view embedding it.
  * @return {number} The height of the content, in pixels.
  */
 function getContentHeight() {
   return $('container').clientHeight;
 }
+
+/**
+ * Removes all header images from the promo.
+ */
+function removeHeaderImages() {
+  var images = document.querySelectorAll('.header-image');
+  for (var i = 0, length = images.length; i < length; i++) {
+    var image = images[i];
+    var parent = image.parentElement;
+    if (parent) {
+      parent.removeChild(image);
+    }
+  }
+}