This needs a zone with transitions near the epoch; and the only CET
with DST that winter was Italy (copied by Malta), for which the Olson
database had a recent (2016) correction to its data, for that winter.
That means we get inconsistent results on O/Sen of different ages.
So add a separate testEpochTranPrivate(), alongside testCetPrivate(),
and test it with America/Toronto. (Unfortunately, MS-Win gets the
date wrong on the first transition after the epoch, so we have to code
round that.)
Since information before the epoch isn't reliably available, only test
the search backwards if nextTransition does find something before it.
(We can safely assume all real transitions happened since 1601;
non-celestial time-keeping wasn't accurate enough, before that, for
anyone to synchronize with anything but celestial time.)
Change-Id: I984b46938a2805b93bb2afd6855e317b5d66b386
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
8b628bb251