Bug 1290116 P4 Verify that unregister waits for active worker to go idle. r=asuth

          assert_equals(registration.active, new_worker);

        });

  }, 'skipWaiting bypasses no controllee requirement');

// This test is not really about activation, but otherwise is very

// similar to the other tests here.

promise_test(t => {

    var scope = 'resources/unregister';

    var worker_url = 'resources/mint-new-worker.py';

    var registration;

    var iframe;

    var new_worker;

    return setup_activation_test(t, scope, worker_url)

      .then(result => {

          registration = result.registration;

          iframe = result.iframe;

          // Remove the iframe.

          iframe.remove();

          return registration.unregister();

        })

      .then(() => {

          // The unregister operation should wait for the active worker to

          // finish processing its events before clearing the registration.

          new_worker = registration.waiting;

          var reached_redundant = wait_for_state(t, new_worker, 'redundant');

          registration.active.postMessage('go');

          return reached_redundant;

        })

      .then(() => {

          assert_equals(registration.installing, null);

          assert_equals(registration.waiting, null);

          assert_equals(registration.active, null);

        });

  }, 'finishing a request triggers unregister');

</script>