code: public void broadcastSubscriptionChanged(String subscriptionName,
              String changetype, String docId) {
          Intent broadcastIntent = new Intent();
          broadcastIntent.setAction(MESSAGE_SUBUPDATED);
          broadcastIntent.putExtra(MESSAGE_EXTRA_SUBNAME, subscriptionName);
          broadcastIntent.putExtra(MESSAGE_EXTRA_CHANGETYPE, changetype);
          broadcastIntent.putExtra(MESSAGE_EXTRA_CHANGEID, docId);        
          LocalBroadcastManager.getInstance(mContext)
                  .sendBroadcast(broadcastIntent);
      }
docs: Used to notify event system of subscription change events.
  Default behavior uses Android's LocalBroadcastManager.
  Override if you want to use a different eventbus.
  @param subscriptionName subscription name (this can be different from collection name)
  @param changetype "change", "add" or "remove"
  @param docId document ID of change/remove or null if add