[WPF] Fix method for getting the native image
[WPF] Fix method for getting the native image

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