void StringBody::Dump(std::ostream& os, const std::string& prefix) const {
  if (!data_.empty()) {
    utility::DumpByLine(data_, os, prefix);
  }
}
void StringBody::Dump(std::ostream& os, const std::string& prefix) const {
  if (!data_.empty()) {
    utility::DumpByLine(data_, os, prefix);
  }
}