title: Display firebase notification data-message on Android tray
body: <p>I need to use non-collapsible notification by Firebase. For that I am using data-message like this:</p>
  
  <pre><code>{
   "to" : "bk3RNwTe3H0:CI2k_HHwgIpoDKCIZvvDMExUdFQ3P1...",
   "data" : {
     "Nick" : "Mario",
     "body" : "great match!",
     "Room" : "PortugalVSDenmark"
    },
  }
  </code></pre>
  
  <p>This message is interpreted in the onMessageReceived() method.
  I still want to display this data-message in the tray just like notification-messages are displayed by the system automatically. </p>
  
  <p>How to I achieve this? I cannot find documentation on this.</p>
  
  <p>Thanks!</p>