chromium/third_party/blink/web_tests/fast/events/keydown-remove-frame.html

<p>
    Tests that WebKit does not crash when a frame is removed during keydown
    event processing. To test manually, press any letter key. The iframe
    below should disappear and Safari should not crash.
</p>
<script>
    function test() {
        document.getElementById("iframe").focus();
        if (window.testRunner) {
            testRunner.dumpAsText();
            eventSender.keyDown("x");
        }
    }
</script>
<iframe onload="test()" id="iframe" src="resources/keydown-remove-frame-iframe.html"></iframe>