<html>
 <head>
   <script>
     if (window.testRunner)
       testRunner.dumpAsText();
   </script>

   <style media="all" type="text/css">
      body {
        display: -webkit-box;
      }

      .test {
        margin-right: -1000000;
        overflow-y: auto;
      }
    </style>
  </head>

  <body>
    <!-- This would previously trigger an assertion failure. Thanks to Robert
         Swiecki for the test case. -->

    <form class="test">
      <select class="test">
        <option>1</option>
      </select>
    </form>

    <p>PASS</p>
  </body>
</html>