std::string(result.error_message()).data());
    if (TF_GetCode(&s) != TF_Code::TF_OK) {
      tensorflow::CoordinationServiceError error;
      *error.mutable_source_task() = result.error_payload().source_task();
      TF_SetPayload(&s, tensorflow::CoordinationErrorPayloadKey().data(),
                    error.SerializeAsString().c_str());
    }
    *state_iter = std::move(s);
    ++state_iter;
  }

        control Tensor-Float-32 evaluation in RNNs.
    *   Added a 'experimental_payloads' field to tf.errors.OpError and its
        subclasses to support more detailed error reporting. This is inspired
        from Abseil Status payloads:
        https://github.com/abseil/abseil-cpp/blob/master/absl/status/status.h

*   `tf.summary`: