[perl #120973] [BUG] Cross product with a .map in the rhs yields an empty list in Rakudo

[Christian Bartolomaeus via RT]

This works now:

$ perl6 -e 'say <a b> X <c d>.map({$_})'
a c a d b c b d

$ perl6 -e 'say <a b>.map({$_}) X <c d>'
a c a d b c b d

$ perl6 -e 'say <a b>.map({$_}) X <c d>.map({$_})'
a c a d b c b d

I added tests to S03-metaops/cross.t with commit 
https://github.com/perl6/roast/commit/d3aa62b272

I'm closing this ticket.