[perl #120992] Nil disappears in junction lists

[Christian Bartolomaeus via RT]

This works now:

< bartolin>  r: say all("a", "b") ~~ /a/ # RT #120992
<+camelia>   rakudo-{moar,jvm} 5d83db: OUTPUT«all(｢a｣, Nil)␤»

I added a test to S03-junctions/misc.t with commit 
https://github.com/perl6/roast/commit/50c2c6c8d9

I'm closing this ticket as 'resolved'.