mozilla-release/layout/reftests/position-dynamic-changes/vertical/toauto-topN-heightA-bottomN.html

<!DOCTYPE html>
<html class="reftest-wait">
  <head>
    <link rel="stylesheet" type="text/css" href="style.css">
    <script src="animate.js" type="text/javascript"></script>
    <script src="../handleprop.js" type="text/javascript"></script>
  </head>
  <body>
    <div id="parent">
      <div id="child" style="top: 100px; bottom: 20px;">
        <div class="floatTop"></div>
        <div class="floatTop"></div>
      </div>
    </div>
    <script>
      toAuto("top");
    </script>
  </body>
</html>