message: Batching fix for when num_batching_threads is 0.
diff: @@ -702,8 +702,15 @@ Status BatchResourceBase::LookupOrCreateBatcherQueue(const string& queue_name,
  ProcessFuncBatch(std::move(batch));
  }
  };
  + if (batcher_) {
  TF_RETURN_IF_ERROR(batcher_->AddQueue(batcher_queue_options_,
  process_batch_callback, &new_queue));
  + } else if (adaptive_batcher_) {
  + TF_RETURN_IF_ERROR(adaptive_batcher_->AddQueue(
  + adaptive_batcher_queue_options_, process_batch_callback, &new_queue));
  + } else {
  + return errors::Internal("No batcher defined.");
  + }
  *queue = new_queue.get();
  batcher_queues_[queue_name] = std::move(new_queue);
  return Status::OK();
  