title: how get message body when FCM notification message is tap?
body: <p>When app is in background,  the notification message is deliver by Notification, when the notification is tap, app is launch, how can i get the message body?</p>
  
  <p>the intent is this:</p>
  
  <pre><code>    Bundle[{google.sent_time=1470813025421, from=568540028909, 
  google.message_id=0:1470813025865549%31bd1c9631bd1c96,
   collapse_key=com.google.firebase.quickstart.fcm}]
  </code></pre>
  
  <p>no message body in intent, only message id!
  Thanks!   </p>