Merge "Use std::optional instead of std::unique_ptr"

  // TODO(jpawlowski) make type casting nicer

  // uuid won't really keep ownership, it's just for type casting

  std::unique_ptr<UUID> uuid;

  UUID tmp;

  std::optional<UUID> uuid;

  if (service_uuid_) {

    tmp = *service_uuid_;

    uuid.reset(&tmp);

  } else {

    uuid.reset(nullptr);

    uuid = *service_uuid_;

  }

  status = parcel->writeNullableParcelable(uuid);

  uuid.release();

  if (status != OK) return status;

  uuid.reset();

  if (service_uuid_mask_) {

    tmp = *service_uuid_mask_;

    uuid.reset(&tmp);

  } else {

    uuid.reset(nullptr);

    uuid = *service_uuid_mask_;

  }

  status = parcel->writeNullableParcelable(uuid);

  uuid.release();

  return status;

}