chromium/third_party/blink/web_tests/external/wpt/service-workers/service-worker/fetch-header-visibility.https.html

<!DOCTYPE html>
<title>Service Worker: Visibility of headers during fetch.</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/common/get-host-info.sub.js"></script>
<script src="resources/test-helpers.sub.js"></script>
<body>
<script>
  var worker = 'resources/fetch-rewrite-worker.js';
  var path = base_path() + 'resources/fetch-access-control.py';
  var host_info = get_host_info();
  var frame;

  promise_test(function(t) {
    var scope = 'resources/fetch-header-visibility-iframe.html';
    return service_worker_unregister_and_register(t, worker, scope)
      .then(function(reg) {
        t.add_cleanup(function() {
            return service_worker_unregister(t, scope);
          });

        return wait_for_state(t, reg.installing, 'activated');
      })
      .then(function() {
        frame = document.createElement('iframe');
        frame.src = scope;
        document.body.appendChild(frame);

        // Resolve a promise when we recieve 2 success messages
        return new Promise(function(resolve, reject) {
          var remaining = 4;
          function onMessage(e) {
            if (e.data == 'PASS') {
              remaining--;
              if (remaining == 0) {
                resolve();
              } else {
                return;
              }
            } else {
              reject(e.data);
            }

            window.removeEventListener('message', onMessage);
          }
          window.addEventListener('message', onMessage);
        });
      })
      .then(function(result) {
        frame.remove();
      });
  }, 'Visibility of defaulted headers during interception');
</script>
</body>