LayoutTests/editing/text-iterator/text-iterator-document-mutation.html

<div id=div>text</div>
<script>
if (window.testRunner)
    testRunner.dumpAsText();

div.offsetLeft;
if (window.internals)
    internals.retainTextIteratorForDocumentContent();
div.textContent = "This test passes if it doesn't crash";
</script>