internal GregorianCalendarHelper(Calendar cal, EraInfo[] eraInfo) {
m_Cal = cal;
m_EraInfo = eraInfo;
// m_minDate is existing here just to keep the serialization compatibility.
// it has nothing to do with the code anymore.
m_minDate = m_Cal.MinSupportedDateTime;
m_maxYear = m_EraInfo[0].maxEraYear;
m_minYear = m_EraInfo[0].minEraYear;;
}