Parses a field value into a Date. A date-only value arrives as UTC midnight (or a bare
yyyy-mm-dd string, which JavaScript also reads as UTC); its UTC calendar day becomes local
midnight, so it never shifts a day west of Greenwich. Returns null for empty or invalid values.
Parses a field value into a Date. A date-only value arrives as UTC midnight (or a bare
yyyy-mm-ddstring, which JavaScript also reads as UTC); its UTC calendar day becomes local midnight, so it never shifts a day west of Greenwich. Returns null for empty or invalid values.