message: Use VLOG(1) instead of LOG(WARNING) if TRT is called on funcdefs
  This cleans up the log in TF2.0
diff: @@ -183,9 +183,11 @@ Status TRTOptimizationPass::Optimize(grappler::Cluster* cluster,
  // generated funcdefs! This is fragile but we don't have any other option
  // until framework fixes it.
  if (item.id != "tf_graph") {
  - LOG(WARNING) << name_
  - << " is probably called on funcdef! This optimizer must *NOT* "
  - "be called on function objects.";
  + VLOG(1) << "Called TRTOptimization Pass " << name_
  + << " on a grappler item with id=" << item.id
  + << ", which is probably a function object (funcdef). "
  + << "Skipping optimization because TensorRTOptimizer "
  + << "should not be called on function objects.";
  *optimized_graph = item.graph;
  return Status::OK();
  }
  