message: Improving readability by using Cluster::NumWarmupSteps() instead of directly calling options_.config.graph_options().build_cost_model_after()
diff: @@ -181,8 +181,7 @@ Status SingleMachine::Run(const GraphDef& graph_def,
  }
  // Warmup TensorFlow if needed
  - for (int i = 0;
  - i < options_.config.graph_options().build_cost_model_after(); ++i) {
  + for (int i = 0; i < NumWarmupSteps(); ++i) {
  TF_RETURN_IF_ERROR(RunWithTimeout(feed, fetch, nullptr));
  }
  }
  