[AST] Fix friendship with AnyRequestBase
[AST] Fix friendship with AnyRequestBase

This was causing issues with MSVC. Have subclasses
be friends with all specializations of
AnyRequestBase, and define `getRawStorage` in
the base class to make it accessible to `friend`
top-level functions.

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