message: Fix unexpected type 0 crash in saved model loader
diff: @@ -1356,6 +1356,13 @@ Status ConstantFolding::EvaluateOneFoldable(const NodeDef& node,
  }
  TF_RETURN_IF_ERROR(CheckAttrExists(*input_node, "value"));
  const TensorProto& raw_val = input_node->attr().at("value").tensor();
  + if (raw_val.dtype() == DT_INVALID) {
  + return Status(
  + error::INVALID_ARGUMENT,
  + strings::StrCat("A tensor in the input node, with TensorId of ",
  + input_tensor.ToString(),
  + " has a dtype of DT_INVALID."));
  + }
  Tensor* value = new Tensor(raw_val.dtype(), raw_val.tensor_shape());
  if (!value->FromProto(raw_val)) {
  delete (value);
  