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

function onloadHandler() {
    shadow = document.createElement("div").attachShadow({mode: "closed"});
    shadow.prepend(dataElement);
}
</script>
<body>
  <data id="dataElement">
    <table id="theTable">
      <iframe id="theIframe" onload="onloadHandler()"></iframe>
      <hr id="FOO"/>
    </table>
  </data>
  <p>
    This test passes if it doesn't crash.
  </p>
</body>