Method FindMember

include/sonic/dom/dynamicnode.h:247–250

   * std::memcmp while length is not too large.
   */
  sonic_force_inline MemberIterator FindMember(const char* key,
                                               size_t len) noexcept {
    return findMemberImpl(key, len);
  }

  /**
   * @brief Find a specific member in an object. A member is a pair node of key