third_party/blink/web_tests/http/tests/xmlhttprequest/resources/cross-origin-preset-authorization-frame.html

<script>
// Good for both cross-origin-no-authorization and cross-origin-authorization, which only differ in cross-origin case.
var req = new XMLHttpRequest;
req.open("GET", "cross-origin-no-authorization.php", false, "test", "test");
req.send();
opener.postMessage("test", "*");
window.close();
</script>
<p>This frame sets up authorization for another origin.</p>