title: Update notification adding new lines to the current one
body: <p>I want to show a GCM notification which is multiline, and that notification should be updated by adding new lines. I mean, I receive and show a first notification, then it is shown showing the text "Notification 1". But then, when a second notification is received, I want to update the current active notification by adding a second line that says "Notification 2". How could I achieve that? I've thought about setting the NotificationCompat.InboxStyle as static, so the lines may be added, but the problem then is: How could I clear that static data if there's no click callback? I can do it on the PendingIntent, but I think that it would not be a nice way to proceed.</p>
  
  <p>Thanks in advance</p>