<html>
<body>
<div id="shadow">
<iframe src="resources/slow-iframe.py"></iframe>
</div>

<div id="empty"></div>
</body>

<script>
if (window.testRunner) {
    testRunner.dumpAsText();
    testRunner.waitUntilDone();
}

function set2() {
  document.getElementById("shadow").innerHTML = "";
}

function set1() {
  document.getElementById("empty").innerHTML = document.getElementById("shadow").innerHTML;
  setTimeout(set2, 250);
}

setTimeout(set1, 250);
</script>
</html>