<!DOCTYPE html>
<html>
<head>
  <style>
  .composited {
    -webkit-transform: translateZ(0);
  }
  
  .box {
    margin: 10px;
    width: 100px;
    height: 100px;
    z-index: 0;
  }

  .resizable {
    overflow: auto;
    resize: both;
  }
  </style>
  <script type="text/javascript" charset="utf-8">
    if (window.testRunner)
        testRunner.dumpAsText();

    function doTest()
    {
        if (window.testRunner)
          document.getElementById('layers').innerText = window.internals.layerTreeAsText(document);
    }
    
    window.addEventListener('load', doTest, false);
  </script>
  </head>
<body>
  <!-- You should see the resize widget in this element -->
  <div class="resizable composited box"></div>
  <pre id="layers">Layer tree appears here in DRT.</pre>
</body>
</html>