message: Fix a dtype CHECK failure in saved model loader.
diff: @@ -100,6 +100,11 @@ REGISTER_OP("RestoreV2")
  // Attempt to infer output shapes from its shape_and_slice input.
  const Tensor* shape_and_slices_tensor = c->input_tensor(2);
  if (shape_and_slices_tensor) {
  + if (shape_and_slices_tensor->dtype() != DT_STRING) {
  + return errors::InvalidArgument(
  + "Expected an input tensor of type string.");
  + }
  +
  const auto& shape_and_slices_flat =
  shape_and_slices_tensor->flat<tstring>();
  if (shape_and_slices_flat.size() != c->num_outputs()) {
  