third_party/WebKit/LayoutTests/http/tests/serviceworker/resources/fetch-access-control-login.html

<script>
// Set authentication info
var port;
var w;
window.addEventListener("message", function(evt) {
  if (evt.ports[0]) {
    port = evt.ports[0];
    document.cookie = 'cookie=' + evt.data.cookie;
    w = window.open(window.location.protocol + "//" + evt.data.username + ":" + evt.data.password + "@" + window.location.hostname + ":" + window.location.port + "/serviceworker/resources/fetch-access-control.php?Auth&WINDOW", evt.data.username);
  } else {
    w.close();
    w = null;
    port.postMessage({msg: 'LOGIN FINISHED'});
  }
}, false);
</script>