[prespecialized metadata] Allow existential arguments.
[prespecialized metadata] Allow existential arguments.

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