There was no good reason for QEventPoint::pressTimestamp() to be
missing. The case for QEventPoint::timestamp() is a bit dubious
because it's redundant with QInputEvent::timestamp(); but for now,
we keep m_timestamp, in anticipation that Qt Quick may need to keep
copies of eventpoints between events, thus they need to avoid depending
on their shorter-lived parent events too much.
Change-Id: Iec38acfdfaa2afb3dc77d5cd1b95baa8d301c0fd
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>