fix the expansion of beginner-true and beginner-false so they don't throw away source locations.
fix the expansion of beginner-true and beginner-false so
they don't throw away source locations.

related to PR 12253

mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket