chromium/src/third_party/blink/web_tests/http/tests/cache/sync-xhr-304.html

Send 2 sync xhrs to the same url such that the 2nd should return a 304. Ensure that the responseText for the 2nd XHR is non-empty.<br>
<script>
if (window.testRunner)
    testRunner.dumpAsText();

var xhr = new XMLHttpRequest();
xhr.open("GET", "resources/etag.php", false);
xhr.send(null);

var xhr2 = new XMLHttpRequest();
xhr2.open("GET", "resources/etag.php", false);
xhr2.send(null);

document.body.appendChild(document.createTextNode("xhr2.responseText: " + xhr2.responseText));

</script>