<!DOCTYPE HTML>
<title>Testcase, bug 845837</title>
<meta charset="UTF-8">
<!--
https://bugzilla.mozilla.org/show_bug.cgi?id=845837
-->

<div style="height: 20px"></div>

<table border>
  <tr id="tr" style="position: relative">
    <td>hello
</table>

<script>
var tr = document.getElementById("tr");
tr.offsetTop;
tr.style.top = '20px';
tr.offsetTop;
tr.style.fontSize = '100px';
tr.offsetTop;
tr.style.fontSize = '';
tr.offsetTop;
tr.style.top = '0px';
tr.offsetTop;
// Just check that we have no relative positioning applied when we're done,
// since we don't currently support relative positioning on table rows.
</script>