I'm using the recently release [FCM messaging](https://firebase.google.com/docs/cloud-messaging/js/client) support for push notifications on the chrome. When my app is in the background, I get the notification but nothing happens when I click the notification. How to I specify the URL which should open when the user clicks the notification? (I understand how its done using the pure service worker concept using the notificationclick event, I want to know how to do that using [FCM messaging](https://firebase.google.com/docs/cloud-messaging/js/client).)

```
messaging.setBackgroundMessageHandler(function(payload) {
  var data = payload || {};
  var shinyData = decoder.run(data);

  console.log('[firebase-messaging-sw.js] Received background message ', shinyData);

  return self.registration.showNotification(shinyData.title, {
    body: shinyData.body,
    icon: shinyData.icon
  })
});

```

What am I missing here?