[AST] NFC: Add llvm_unreachable() to getOwnership()
[AST] NFC: Add llvm_unreachable() to getOwnership()

If one adds a new reference storage type, then this change is helpful.

stephentyrone/swift,shahmishal/swift,shajrawi/swift,JGiola/swift,practicalswift/swift,parkera/swift,gribozavr/swift,return/swift,lorentey/swift,jckarter/swift,JGiola/swift,tjw/swift,airspeedswift/swift,jopamer/swift,jckarter/swift,tkremenek/swift,benlangmuir/swift,sschiau/swift,jopamer/swift,austinzheng/swift,xwu/swift,gregomni/swift,natecook1000/swift,brentdax/swift,xwu/swift,brentdax/swift,uasys/swift,parkera/swift,practicalswift/swift,rudkx/swift,brentdax/swift,frootloops/swift,devincoughlin/swift,hooman/swift,airspeedswift/swift,OscarSwanros/swift,sschiau/swift,amraboelela/swift,jopamer/swift,hooman/swift,shajrawi/swift,ahoppen/swift,CodaFi/swift,alblue/swift,shahmishal/swift,aschwaighofer/swift,lorentey/swift,ahoppen/swift,OscarSwanros/swift,gribozavr/swift,huonw/swift,practicalswift/swift,danielmartin/swift,xwu/swift,stephentyrone/swift,airspeedswift/swift,shahmishal/swift,amraboelela/swift,xedin/swift,parkera/swift,lorentey/swift,stephentyrone/swift,tkremenek/swift,glessard/swift,milseman/swift,sschiau/swift,milseman/swift,danielmartin/swift,hooman/swift,jopamer/swift,jckarter/swift,frootloops/swift,gregomni/swift,brentdax/swift,apple/swift,benlangmuir/swift,huonw/swift,gregomni/swift,austinzheng/swift,airspeedswift/swift,nathawes/swift,return/swift,amraboelela/swift,xedin/swift,karwa/swift,jckarter/swift,brentdax/swift,frootloops/swift,CodaFi/swift,xwu/swift,apple/swift,tjw/swift,tkremenek/swift,natecook1000/swift,xedin/swift,hooman/swift,ahoppen/swift,ahoppen/swift,glessard/swift,xedin/swift,hooman/swift,harlanhaskins/swift,parkera/swift,apple/swift,swiftix/swift,allevato/swift,CodaFi/swift,lorentey/swift,shajrawi/swift,devincoughlin/swift,karwa/swift,gribozavr/swift,return/swift,zisko/swift,parkera/swift,stephentyrone/swift,jmgc/swift,uasys/swift,jmgc/swift,danielmartin/swift,airspeedswift/swift,roambotics/swift,zisko/swift,devincoughlin/swift,austinzheng/swift,uasys/swift,swiftix/swift,nathawes/swift,atrick/swift,harlanhaskins/swift,aschwaighofer/swift,atrick/swift,stephentyrone/swift,austinzheng/swift,practicalswift/swift,xedin/swift,atrick/swift,xwu/swift,tkremenek/swift,devincoughlin/swift,roambotics/swift,OscarSwanros/swift,zisko/swift,zisko/swift,jopamer/swift,lorentey/swift,aschwaighofer/swift,tkremenek/swift,hooman/swift,ahoppen/swift,practicalswift/swift,roambotics/swift,gregomni/swift,glessard/swift,danielmartin/swift,tjw/swift,shahmishal/swift,danielmartin/swift,stephentyrone/swift,harlanhaskins/swift,natecook1000/swift,gregomni/swift,benlangmuir/swift,gregomni/swift,karwa/swift,swiftix/swift,xedin/swift,apple/swift,airspeedswift/swift,shajrawi/swift,OscarSwanros/swift,practicalswift/swift,jmgc/swift,harlanhaskins/swift,sschiau/swift,lorentey/swift,huonw/swift,apple/swift,gribozavr/swift,austinzheng/swift,nathawes/swift,aschwaighofer/swift,swiftix/swift,huonw/swift,jopamer/swift,practicalswift/swift,nathawes/swift,huonw/swift,milseman/swift,JGiola/swift,sschiau/swift,karwa/swift,alblue/swift,swiftix/swift,xedin/swift,stephentyrone/swift,harlanhaskins/swift,brentdax/swift,amraboelela/swift,milseman/swift,jmgc/swift,CodaFi/swift,harlanhaskins/swift,brentdax/swift,milseman/swift,rudkx/swift,devincoughlin/swift,gribozavr/swift,parkera/swift,huonw/swift,sschiau/swift,roambotics/swift,nathawes/swift,frootloops/swift,austinzheng/swift,karwa/swift,rudkx/swift,swiftix/swift,gribozavr/swift,milseman/swift,devincoughlin/swift,zisko/swift,xwu/swift,zisko/swift,CodaFi/swift,nathawes/swift,allevato/swift,uasys/swift,sschiau/swift,karwa/swift,JGiola/swift,jmgc/swift,JGiola/swift,alblue/swift,return/swift,OscarSwanros/swift,allevato/swift,alblue/swift,lorentey/swift,danielmartin/swift,allevato/swift,danielmartin/swift,practicalswift/swift,zisko/swift,roambotics/swift,natecook1000/swift,allevato/swift,jckarter/swift,frootloops/swift,shajrawi/swift,aschwaighofer/swift,benlangmuir/swift,devincoughlin/swift,jmgc/swift,benlangmuir/swift,atrick/swift,return/swift,parkera/swift,OscarSwanros/swift,ahoppen/swift,gribozavr/swift,frootloops/swift,rudkx/swift,tjw/swift,tjw/swift,rudkx/swift,jckarter/swift,natecook1000/swift,karwa/swift,jckarter/swift,natecook1000/swift,tkremenek/swift,tjw/swift,shahmishal/swift,shajrawi/swift,jopamer/swift,amraboelela/swift,huonw/swift,alblue/swift,nathawes/swift,CodaFi/swift,OscarSwanros/swift,lorentey/swift,jmgc/swift,alblue/swift,atrick/swift,JGiola/swift,shahmishal/swift,shahmishal/swift,hooman/swift,xedin/swift,natecook1000/swift,aschwaighofer/swift,tjw/swift,austinzheng/swift,airspeedswift/swift,swiftix/swift,milseman/swift,karwa/swift,apple/swift,benlangmuir/swift,shajrawi/swift,CodaFi/swift,frootloops/swift,roambotics/swift,allevato/swift,rudkx/swift,sschiau/swift,glessard/swift,gribozavr/swift,glessard/swift,parkera/swift,atrick/swift,shahmishal/swift,uasys/swift,uasys/swift,tkremenek/swift,return/swift,glessard/swift,aschwaighofer/swift,return/swift,uasys/swift,alblue/swift,amraboelela/swift,xwu/swift,allevato/swift,amraboelela/swift,devincoughlin/swift,shajrawi/swift,harlanhaskins/swift