In QTimeZonePrivate::dataForLocalTime(), mistrust the Android
backend's hasDaylightTime(), as it has a comment saying it only knows
about future transitions, not past. This caller of it really needs to
query "has ever had a transition", which this doesn't answer. Many
zones that have no plans for future transitions have had transitions
in the past; these were failing the transitionEachZone() test.
In the process, refine the test itself, making sure we catch some
quirk cases that shouldn't arise and making the debug message on
failure more informative (while eliding the zone name, as this is part
of the test name anyway, so added to the output by qDebug() itself).
Fixes: QTBUG-69131
Change-Id: I88a0528182c247acb8b6327b40516178e455bcc0
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>