<!DOCTYPE html>
<script>
    if (window.testRunner)
        testRunner.dumpAsText();
</script>
<p>PASS if no crash or assertion failure.</p>
<div style="-webkit-columns:3;">
    <button style="display:block;">
        <div style="-webkit-column-span:all;"></div>
    </button>
    &nbsp;
</div>