title: Notification doesn't appear in foreground service
body: <p>I'm using the following code:</p>
  
  <pre><code>private void startForeground(boolean isActive) {
          Intent notificationIntent = new Intent(this, MainActivity.class);
          PendingIntent pendingIntent = PendingIntent.getActivity(this, 1, notificationIntent, PendingIntent.FLAG_UPDATE_CURRENT);
  
          Notification notification = new NotificationCompat.Builder(this)
                  .setSmallIcon(R.mipmap.ic_launcher)
                  .setContentTitle(getString(isActive ? R.string.title_agent_active : R.string.title_agent_inactive))
                  .setContentIntent(pendingIntent)
                  .build();
  
          startForeground(1, notification);
      }
  </code></pre>
  
  <p>and </p>
  
  <pre><code> @Override
      protected void onHandleIntent(Intent intent) {
          startForeground(true);
          ...
  </code></pre>
  
  <p>With this code notification does not appear.</p>
  
  <p>But if I replace startForeground(...) with NotificationManager.notify(...) — it shows the notification, so, I think, that at least notification building code is ok.</p>
  
  <p>Where could be the problem? </p>