<!DOCTYPE html>

<html>
<head>
  <style>
    #container {
      position: relative;
      width: 400px;
      height: 100px;
      border: 1px solid  black;
    }
    
    .box {
      position: absolute;
      width: 100px;
      height: 100px;
      background-color: green;
    }
    
    .indicator {
      left: 0;
      top: 0;
      background-color: red;
    }

    #container.moved .hardware {
      animation: move 300ms linear;
    }

    @keyframes move {
      from { left: 0; }
      to   { left: 300px; }
    }
   </style>

   <script type="text/javascript">
    function testEnded()
    {
      if (window.testRunner)
        testRunner.notifyDone();
    }
    
    function startTest()
    {
      if (window.testRunner)
        testRunner.waitUntilDone();

      document.getElementById('tester').addEventListener('animationend', testEnded, false);
      document.getElementById('container').offsetTop; // Force style recalc
      document.getElementById('container').className = 'moved';
    }
    
    window.addEventListener('load', startTest, false);
   </script>
</head>
<body>

  <p>At the end of the test the green box should obscure the red box.</p>
  <div id="container">
    <div class="indicator box"></div>
    <div id="tester" class="hardware box"></div>
  </div>

  <div id="result"></div>

</body>
</html>