@Override
  public void toData(final DataOutput out,
      SerializationContext context) throws IOException {
    super.toData(out, context);
    DataSerializer.writeObject(callbackArg, out);
  }
Sends a DestroyRegionOnDataStoreMessage requesting that another VM destroy an existing region
geode-core/src/main/java/org/apache/geode/internal/cache/partitioned/DestroyRegionOnDataStoreMessage.java