gecko-dev/image/test/unit/test_async_notification_404.js

/*
 * Test to ensure that load/decode notifications are delivered completely and
 * asynchronously when dealing with a file that's a 404.
 */
/* import-globals-from async_load_tests.js */

var ioService = Services.io;

// This is used in async_load_tests.js
// eslint-disable-next-line no-unused-vars
ChromeUtils.defineLazyGetter(this, "uri", function () {
  return ioService.newURI(
    "http://localhost:" +
      server.identity.primaryPort +
      "/async-notification-never-here.jpg"
  );
});

load("async_load_tests.js");