[MAC] fix popver positioning for empty position rect.
[MAC] fix popver positioning for empty position rect.

sevoku/xwt,residuum/xwt,lytico/xwt,TheBrainTech/xwt,steffenWi/xwt,cra0zy/xwt,hamekoz/xwt,mono/xwt,directhex/xwt,hwthomas/xwt,mminns/xwt,antmicro/xwt,mminns/xwt,akrisiun/xwt,iainx/xwt