chromium/third_party/blink/web_tests/http/tests/webfont/font-load-revalidation.html

<!doctype html>
<html>
<head>
<script src="/js-test-resources/js-test.js"></script>
</head>
<body>
<script>
jsTestIsAsync = true;

var reloaded = false;

window.addEventListener('message', e => {
  var message = e.data.split(':');
  if (message[0] == 'reload') {
    if (!reloaded) {
      reloaded = true;
      frames[0].location.reload();
    } else {
      finishJSTest();
    }
  } else if (message[0] == 'pass') {
    testPassed(message[1]);
  } else {
    testFailed(message[1]);
  }
});

</script>
<iframe id="iframe" src="resources/font-load-revalidation-frame.html"></iframe>
</body>
</html>