[WPF] Canvas: Clip the drawing area
[WPF] Canvas: Clip the drawing area

Fixes issue when drawing outside the canvas bounds.

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