Function setEmptyString

include/sonic/dom/genericnode.h:1052–1055

    return downCast()->setRawImpl(s.data(), s.size());
  }
  void setEmptyString() noexcept {
    sv.p = "";
    setLength(0, kStringConst);
  }

  sonic_force_inline int64_t getIntMax() const {
    return std::numeric_limits<int>::max();