<!DOCTYPE HTML>
<html>
<!--
https://bugzilla.mozilla.org/show_bug.cgi?id=509244
-->
<head>
  <title>Test for Bug 509244</title>
  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
</head>
<body>
<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=509244">Mozilla Bug 509244</a>
<p id="display">A</p>
<div id="content" style="display: none">
  
</div>
<pre id="test">
<script type="application/javascript">

/** Test for Bug 509244 **/

function flush() { document.documentElement.offsetHeight; }

var text = document.getElementById("display");

// layout text, caching monospace font
text.style.fontFamily = "monospace";
flush();
// relayout text so that monospace font is no longer used (but cached)
text.style.fontFamily = "sans-serif";
flush();

// flush cache
var os = SpecialPowers.Cc["@mozilla.org/observer-service;1"]
         .getService(SpecialPowers.Ci.nsIObserverService);
os.notifyObservers(null, "memory-pressure", "heap-minimize");

// reuse font that was flushed from cache
text.style.fontFamily = "monospace";
flush(); 

ok(true, "not crashed");

</script>
</pre>
</body>
</html>