Merge "Send volume just once when starting the stream."

    BtaGattQueue::WriteCharacteristic(device.conn_id,

                                      device.audio_control_point_handle, start,

                                      GATT_WRITE, nullptr, nullptr);

    // TODO(jpawlowski): this will be removed, once test devices get volume

    // from start reqest

    if (current_volume != VOLUME_UNKNOWN) {

      std::vector<uint8_t> volume_value(

          {static_cast<unsigned char>(current_volume)});

      BtaGattQueue::WriteCharacteristic(device.conn_id, device.volume_handle,

                                        volume_value, GATT_WRITE_NO_RSP,

                                        nullptr, nullptr);

    }

  }

  void OnAudioDataReady(const std::vector<uint8_t>& data) {