[NFC] AST: Push up a fast path in TypeBase::getContextSubstitutions
[NFC] AST: Push up a fast path in TypeBase::getContextSubstitutions

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