document-write-during-onload-still-finishes.html

<html>
<head>
<script>
if (window.testRunner)
    testRunner.dumpAsText();

function loaded()
{
    document.querySelector('#frame').contentDocument.write("We pass if we don't timeout");
}
</script>
</head>
<body onload="loaded();">
<iframe id="frame"></iframe>
</body>
</html>

chromium/third_party/blink/web_tests/fast/loader/document-write-during-onload-still-finishes.html