Update LocalTime partially to 11+28

Imported NANOS_PER_MILLI constant, updated javadocs.

Imported methods:
 * LocalTime ofInstant(Instant, ZoneId)
 * long toEpochSecond(LocalDate, ZoneOffset)

Added unit test from upstream.

Test: n/a
Change-Id: I814f1e9239c5b672e48bd54dabd0703927b91eea
3 files changed