Print Preview: Make getChildElement return required HTMLElement

chrome/browser/resources/print_preview/settings/destination_settings.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.
 
 cr.define('print_preview', function() {
   'use strict';
 
   // TODO(rltoscano): This class needs a throbber while loading the destination
   // or another solution is persist the settings of the printer so that next
   // load is fast.
@@ skipping 132 matching lines @@
         offlineStatusEl.title = offlineStatusText;
 
         var isOffline = destination.isOffline;
         destinationSettingsBoxEl.classList.toggle(
             DestinationSettings.Classes_.STALE, isOffline);
         setIsVisible(locationEl, !isOffline);
         setIsVisible(offlineStatusEl, isOffline);
       }
 
       setIsVisible(
-          assert(this.getChildElement('.throbber-container')),
+          this.getChildElement('.throbber-container'),
           this.destinationStore_.isAutoSelectDestinationInProgress);
-      setIsVisible(assert(destinationSettingsBoxEl), !!destination);
+      setIsVisible(destinationSettingsBoxEl, !!destination);
     },
 
     onSelectedDestinationNameSet_: function() {
       var destinationName =
           this.destinationStore_.selectedDestination.displayName;
       var nameEl = this.getElement().getElementsByClassName(
           DestinationSettings.Classes_.THOBBER_NAME)[0];
       nameEl.textContent = destinationName;
       nameEl.title = destinationName;
     }
   };
 
   // Export
   return {
     DestinationSettings: DestinationSettings
   };
 });