The latter is much faster as it doesn't have to deal with
time zones.
This change is safe, because the QDateTime is only used to
compare against a copy of itself, adjusted by some seconds,
which doen't care which TZ the date-time is in, to get a
time_t, which is much faster done from a UTC time, and
to calculate the seconds to expirationTime, which, from a
quick glance around, seem to be mostly, if not exclusively,
in UTC. secsTo() works across time zones, but the comparison
between UTC date-times is fastest.
Credits to Milian Wolff, from whose QtWS15 talk this advice is
taken.
Change-Id: I22aa5350b29493f01fb503ef5ec68a964ca95cf3
Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>
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