Remove useless $out parameter from SkinTemplate::prepareQuickTemplate()

Part II; follow-up I4fac5b14af (ff4da35).

It makes sufficient time the first part was merged, no need to pass the
parameter anymore.

Change-Id: Icb390995912b4860df4ce2571105d3a9dc97a092
Merge "Remove useless $out parameter from SkinTemplate::prepareQuickTemplate()"