<!DOCTYPE html>
<html>
<head>
<title>This tests that auto transition returns the proper computed value.</title>
<style>
#dropdown {
    font-size: 16px;
    font-family: ahem;
    color: white;
    overflow: hidden;
    border: 1px solid red;
    height: 0px;
    transition: height 1s ease-out;
}
</style>
</head>
<body>
<div id=dropdown>foobar</div>
PASS if you can see foobar above.

<script>
if (window.testRunner)
    testRunner.waitUntilDone();

setTimeout(function() {
    var element = document.getElementById("dropdown");
    element.style.height = 'auto';
    var h = element.offsetHeight;
    element.style.height = h + 'px';
    if (window.testRunner)
        testRunner.notifyDone();
}, 0);
</script>
</body>
</html>