<html>
<body>
<script>
  var key = 'EmptyString';
  var value = '';
  var testKey = 'TestString';
  if (!localStorage.getItem(testKey)) {
    localStorage.setItem(key, value);
    localStorage.setItem(testKey, 'test');
    window.webkit.messageHandlers.testHandler.postMessage("setItem " + key);
  } else {
    window.webkit.messageHandlers.testHandler.postMessage("" + localStorage.getItem(key));
  }
</script>
</body>
</html>