Remove assert() from getChildElement() to fix the bug caused by https://chromiumcodereview.appspot.…

chrome/browser/resources/print_preview/component.js

Index: chrome/browser/resources/print_preview/component.js
diff --git a/chrome/browser/resources/print_preview/component.js b/chrome/browser/resources/print_preview/component.js
index 3437a31a1c6fb62622f60473bdd2c213cb333d97..acf49640d67be0a9406af1391c524ae37b840fe8 100644
--- a/chrome/browser/resources/print_preview/component.js
+++ b/chrome/browser/resources/print_preview/component.js
@@ -154,12 +154,12 @@ cr.define('print_preview', function() {
      * @param {string} query Selector query to select an element starting from
      *     the component's root element using a depth first search for the first
      *     element that matches the query.
-     * @return {!HTMLElement} Element selected by the given query.
+     * @return {HTMLElement} Element selected by the given query.
      * TODO(alekseys): Check all call sites and rename this function to
      *     something like getRequiredChildElement.
      */
     getChildElement: function(query) {
-      return assert(this.element_.querySelector(query));
+      return this.element_.querySelector(query);
     },
 
     /**