[CSClosure] Make sure that partially resolved params/result gets their type variables referenced
[CSClosure] Make sure that partially resolved params/result gets their type variables referenced

It's possible to declare explicit parameter/result type without
providing generic arguments, in such situation they'd be "opened"
as type variables and inferred from the contextual type or the body.

Type variable collector needs to account for that and include
such inner type variables into scope of an isolated closure.

gregomni/swift,apple/swift,apple/swift,xwu/swift,apple/swift,ahoppen/swift,glessard/swift,atrick/swift,atrick/swift,rudkx/swift,rudkx/swift,JGiola/swift,benlangmuir/swift,glessard/swift,gregomni/swift,xwu/swift,atrick/swift,benlangmuir/swift,apple/swift,rudkx/swift,rudkx/swift,xwu/swift,ahoppen/swift,JGiola/swift,xwu/swift,roambotics/swift,rudkx/swift,ahoppen/swift,apple/swift,glessard/swift,roambotics/swift,atrick/swift,apple/swift,glessard/swift,atrick/swift,atrick/swift,gregomni/swift,glessard/swift,xwu/swift,ahoppen/swift,xwu/swift,roambotics/swift,rudkx/swift,benlangmuir/swift,gregomni/swift,JGiola/swift,gregomni/swift,roambotics/swift,benlangmuir/swift,ahoppen/swift,ahoppen/swift,benlangmuir/swift,xwu/swift,JGiola/swift,JGiola/swift,benlangmuir/swift,gregomni/swift,JGiola/swift,roambotics/swift,roambotics/swift,glessard/swift