We are currently in process of removing `InOutType`
so `VarDecl::get{Interface}Type` is going to wrap base
type into `InOutType` if its flag indicates that it's
an `inout` parameter declaration. But such type can't
be restored directly using `VarDecl::set{Interface}Type`
caller needs additional logic to extract base type.
Resolves: rdar://problem/33613329
