message: Add nullptr check when delivering audio
diff: @@ -31,8 +31,10 @@ namespace erizo {
  std::map<std::string, std::shared_ptr<MediaSink>>::iterator it;
  for (it = subscribers.begin(); it != subscribers.end(); ++it) {
  + if ((*it).second != nullptr) {
  (*it).second->deliverAudioData(audio_packet);
  }
  + }
  return 0;
  }
  