Bugfix: Correctly change focus when closing a split-container
Bugfix: Correctly change focus when closing a split-container

The problem was i3 leaving an invalid focus pointer valid (after killing the
container) because the container itself is not mapped (if it has no x11 window,
for example split containers).

i3/i3,Zopieux/i3,mh21/i3,Airblader/i3-original,yin/i3,Zopieux/i3,gnomus/i3-wm-gap,tcreech/i3,drbig/i3,FauxFaux/i3,Phlogistique/i3,i3/i3,Eelis/i3,saksham0808/i3,pablospe/i3,strake/i3,FauxFaux/i3,stapelberg/i3,stfnm/i3,MForster/i3,drbig/i3,FauxFaux/i3,mariusmuja/i3wm,ccryx/i3,strake/i3,sa1/i3,jubalh/i3,stfnm/i3,pronobis/i3,cornerman/i3,saksham0808/i3,jubalh/i3,MForster/i3,netzverweigerer/i3,ccryx/i3,sa1/i3,yin/i3,drbig/i3,gnomus/i3-wm-gap,smrt28/i3,shdown/i3,pablospe/i3,strake/i3,Kaligule/i3,jubalh/i3,dg-ratiodata/i3,Matmusia/i3,ccryx/i3,dg-ratiodata/i3,simonnagl/i3,DSMan195276/i3,i3/i3,stfnm/i3,Kaligule/i3,smrt28/i3,smrt28/i3,gnomus/i3-wm-gap,smrt28/i3,acrisci/i3,sideffect0/i3wm,tcreech/i3,sideffect0/i3wm,jubalh/i3,Zopieux/i3,yin/i3,Chr1stoph/i3,gigawhitlocks/i3-hacking,dtomasiewicz/i3,renlinx007/i3wm,simonnagl/i3,simonnagl/i3,isharp/i3,dtomasiewicz/i3,Airblader/i3-original,Airblader/i3,netzverweigerer/i3,EvilPudding/i3,sideffect0/i3wm,renlinx007/i3wm,Phlogistique/i3,stapelberg/i3,Chr1stoph/i3,ccryx/i3,dg-ratiodata/i3,shdown/i3,netzverweigerer/i3,isharp/i3,mh21/i3,Chr1stoph/i3,mariusmuja/i3wm,Airblader/i3,Airblader/i3,Kaligule/i3,pronobis/i3,tcreech/i3,MForster/i3,stapelberg/i3,netzverweigerer/i3,Azkae/i3,Matmusia/i3,gigawhitlocks/i3-hacking,pronobis/i3,Airblader/i3-original,stfnm/i3,renlinx007/i3wm,stapelberg/i3,avrelaun/i3,i3/i3,acrisci/i3,mariusmuja/i3wm,dg-ratiodata/i3,DSMan195276/i3,sa1/i3,Kaligule/i3,Phlogistique/i3,Matmusia/i3,gigawhitlocks/i3-hacking,avrelaun/i3,renlinx007/i3wm,pronobis/i3,avrelaun/i3,acrisci/i3,saksham0808/i3,dtomasiewicz/i3,mh21/i3,Airblader/i3,EvilPudding/i3,Azkae/i3,DSMan195276/i3,mariusmuja/i3wm,gnomus/i3-wm-gap,Chr1stoph/i3,isharp/i3,acrisci/i3,yin/i3,shdown/i3,mh21/i3,shdown/i3,avrelaun/i3,DSMan195276/i3,dtomasiewicz/i3,cornerman/i3,isharp/i3,Airblader/i3-original,Eelis/i3,cornerman/i3,strake/i3,Azkae/i3,strake/i3,sa1/i3,Matmusia/i3,cornerman/i3,MForster/i3,Eelis/i3,simonnagl/i3,acrisci/i3,Azkae/i3,Airblader/i3-original,pablospe/i3,EvilPudding/i3,Eelis/i3,Zopieux/i3,sideffect0/i3wm,FauxFaux/i3,drbig/i3,pablospe/i3,saksham0808/i3,tcreech/i3,EvilPudding/i3,gigawhitlocks/i3-hacking