A Qt5 program writing a null QTime() using setVersion(QDataStream::Qt_3_3),
and then a Qt3 program reading that, would lead to a weird QTime,
with isNull=false, isValid=false, hour=1193, minute=2, second=47, ms=295.
This commit restores interoperability, by writing out the expected value
(0) for a null QTime rather than the -1 value used by Qt4 and Qt5.
Change-Id: Icde468a8f6fc9434ef7018296725819b44d672af
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
1af4916e11