message: format error message in create op
diff: @@ -91,7 +91,8 @@ class MaxOp : public XlaReductionOp {
  Status TypeCheck(xla::PrimitiveType xla_reduction_type_) {
  if (xla_reduction_type_ == xla::C64) {
  return errors::InvalidArgument(
  - "Unsupported type in xla_reduction_type_");
  + "Unsupported PrimitiveType in MaxOp: '",
  + xla::PrimitiveType_Name(xla_reduction_type_), "'");
  } else {
  return Status::OK();
  }
  