[CSClosure] Start using recorded targets for `ReturnStmt`s
[CSClosure] Start using recorded targets for `ReturnStmt`s

Multi-statement closures and result builder transformed entities
record a target for `return` statement during constraint generation.

Single-statement closure do not but they'd be handled in a special
way.

benlangmuir/swift,apple/swift,JGiola/swift,JGiola/swift,roambotics/swift,glessard/swift,JGiola/swift,benlangmuir/swift,apple/swift,glessard/swift,roambotics/swift,benlangmuir/swift,apple/swift,benlangmuir/swift,roambotics/swift,benlangmuir/swift,apple/swift,glessard/swift,roambotics/swift,apple/swift,glessard/swift,roambotics/swift,roambotics/swift,JGiola/swift,JGiola/swift,benlangmuir/swift,glessard/swift,apple/swift,JGiola/swift,glessard/swift