controller-on-disconnect.https.html

<!DOCTYPE html>
<title>Service Worker: Controller on load</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/test-helpers.sub.js"></script>
<body>
<script>
promise_test(function(t) {
    var url = 'resources/empty-worker.js';
    var scope = 'resources/blank.html';
    var registration;
    var controller;
    var frame;
    return service_worker_unregister_and_register(t, url, scope)
      .then(function(swr) {
          t.add_cleanup(function() {
              return service_worker_unregister(t, scope);
            });

          registration = swr;
          return wait_for_state(t, registration.installing, 'activated');
        })
      .then(function() {
          return with_iframe(scope)
        })
      .then(function(f) {
          frame = f;
          var w = frame.contentWindow;
          var swc = w.navigator.serviceWorker;
          assert_true(swc.controller instanceof w.ServiceWorker,
                      'controller should be a ServiceWorker object');

          frame.remove();

          assert_equals(swc.controller, null,
                        'disconnected frame should not be controlled');
        });
}, 'controller is cleared on disconnected window');
</script>
</body>

chromium/third_party/blink/web_tests/external/wpt/service-workers/service-worker/controller-on-disconnect.https.html