[Constraint application] Stop optimizing casts in the AST.
[Constraint application] Stop optimizing casts in the AST.

Constraint application was rewriting conditional casts (as?) and
forced casts (as!) into coercions (as) at the AST level when it
determined that there was a coercion. Stop doing that: it's the
optimizer's job to remove such casts.

nathawes/swift,karwa/swift,aschwaighofer/swift,nathawes/swift,JGiola/swift,roambotics/swift,rudkx/swift,gribozavr/swift,stephentyrone/swift,roambotics/swift,JGiola/swift,harlanhaskins/swift,aschwaighofer/swift,hooman/swift,tkremenek/swift,allevato/swift,glessard/swift,benlangmuir/swift,karwa/swift,gribozavr/swift,gregomni/swift,jmgc/swift,benlangmuir/swift,nathawes/swift,stephentyrone/swift,tkremenek/swift,ahoppen/swift,harlanhaskins/swift,CodaFi/swift,hooman/swift,allevato/swift,allevato/swift,roambotics/swift,apple/swift,CodaFi/swift,CodaFi/swift,gribozavr/swift,parkera/swift,aschwaighofer/swift,roambotics/swift,atrick/swift,benlangmuir/swift,harlanhaskins/swift,lorentey/swift,xwu/swift,tkremenek/swift,glessard/swift,atrick/swift,harlanhaskins/swift,gribozavr/swift,gribozavr/swift,ahoppen/swift,CodaFi/swift,allevato/swift,hooman/swift,airspeedswift/swift,jckarter/swift,hooman/swift,rudkx/swift,rudkx/swift,gregomni/swift,JGiola/swift,tkremenek/swift,xwu/swift,parkera/swift,karwa/swift,lorentey/swift,ahoppen/swift,tkremenek/swift,roambotics/swift,JGiola/swift,jckarter/swift,jmgc/swift,gribozavr/swift,parkera/swift,nathawes/swift,airspeedswift/swift,CodaFi/swift,karwa/swift,ahoppen/swift,gregomni/swift,xwu/swift,hooman/swift,nathawes/swift,apple/swift,lorentey/swift,harlanhaskins/swift,glessard/swift,jmgc/swift,gregomni/swift,rudkx/swift,aschwaighofer/swift,atrick/swift,rudkx/swift,stephentyrone/swift,stephentyrone/swift,lorentey/swift,gregomni/swift,allevato/swift,stephentyrone/swift,ahoppen/swift,atrick/swift,jmgc/swift,parkera/swift,xwu/swift,gribozavr/swift,benlangmuir/swift,jmgc/swift,allevato/swift,glessard/swift,allevato/swift,glessard/swift,airspeedswift/swift,CodaFi/swift,jckarter/swift,lorentey/swift,karwa/swift,xwu/swift,gribozavr/swift,benlangmuir/swift,harlanhaskins/swift,ahoppen/swift,aschwaighofer/swift,JGiola/swift,hooman/swift,airspeedswift/swift,karwa/swift,tkremenek/swift,parkera/swift,jmgc/swift,parkera/swift,apple/swift,xwu/swift,karwa/swift,jckarter/swift,apple/swift,jckarter/swift,karwa/swift,jckarter/swift,jmgc/swift,nathawes/swift,roambotics/swift,xwu/swift,apple/swift,lorentey/swift,aschwaighofer/swift,glessard/swift,benlangmuir/swift,stephentyrone/swift,parkera/swift,jckarter/swift,nathawes/swift,tkremenek/swift,airspeedswift/swift,CodaFi/swift,rudkx/swift,lorentey/swift,JGiola/swift,apple/swift,hooman/swift,aschwaighofer/swift,atrick/swift,stephentyrone/swift,harlanhaskins/swift,gregomni/swift,lorentey/swift,parkera/swift,airspeedswift/swift,atrick/swift,airspeedswift/swift