Don't overwrite onlineSince if the property is already set.
Don't overwrite onlineSince if the property is already set.

BUG: 212504


svn path=/trunk/KDE/kdenetwork/kopete/; revision=1043341

josh-wambua/kopete,josh-wambua/kopete,Jtalk/kopete-fork-xep0136,Jtalk/kopete-fork-xep0136,Jtalk/kopete-fork-xep0136,josh-wambua/kopete,josh-wambua/kopete,josh-wambua/kopete,josh-wambua/kopete,josh-wambua/kopete,Jtalk/kopete-fork-xep0136,Jtalk/kopete-fork-xep0136,Jtalk/kopete-fork-xep0136