Chrome でデスクトップ通知を表示するにはどうすればよいですか?

<code class="javascript">// Request permission on page load
document.addEventListener('DOMContentLoaded', function() {
 if (!Notification) {
  alert('Desktop notifications not available in your browser. Try Chromium.');
  return;
 }

 if (Notification.permission !== 'granted')
  Notification.requestPermission();
});

// Function to display a notification
function notifyMe() {
 if (Notification.permission !== 'granted')
  Notification.requestPermission();
 else {
  var notification = new Notification('Notification title', {
   icon: 'http://cdn.sstatic.net/stackexchange/img/logos/so/so-icon.png',
   body: 'Hey there! You\'ve been notified!',
  });
  notification.onclick = function() {
   window.open('http://stackoverflow.com/a/13328397/1269037');
  };
 }
}</code>

<code class="html"><button onclick="notifyMe()">Notify me!</button></code>