xmlhttprequest-pagehide-sync-handler-attached-from-parent.html

<!DOCTYPE html>
<html>
<body>
<p>Test behavior of sync XHR during pagehide when the pagehide handler is attached
   to a child iframe from the parent (crbug.com/1044348).</p>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script>
var t = async_test();

onload = () => {
  t.step_timeout(() => {
    var iframe = document.getElementById("ifr");
    iframe.contentWindow.onpagehide = t.step_func(() => {
      try {
        console.log("trying the synx xhr");
        var xhr = new XMLHttpRequest();
        xhr.open("GET", "resources/1251.html", false);
        xhr.send(null);
        assert_unreached('Sync XHR must throw during an pagehide event');
      } catch (e) {
        t.done();
      }
    });
    iframe.src = "about:blank";
  }, 1000);
};

</script>
<iframe id="ifr" name="ifr" src="resources/test.html"></iframe>
</body>
</html>

chromium/third_party/blink/web_tests/http/tests/xmlhttprequest/xmlhttprequest-pagehide-sync-handler-attached-from-parent.html