The Tor Browser / file revision

 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this file,

  * You can obtain one at http://mozilla.org/MPL/2.0/. */

 function run_test() {

   let serv = Cc["@mozilla.org/content-pref/service;1"].

              getService(Ci.nsIContentPrefService2);

   do_check_eq(serv.QueryInterface(Ci.nsIContentPrefService2), serv);

   do_check_eq(serv.QueryInterface(Ci.nsISupports), serv);

   let val = serv.QueryInterface(Ci.nsIContentPrefService);

   do_check_true(val instanceof Ci.nsIContentPrefService);

 }