[m-rev.] for review: don't have the parser return dummy trees

[Zoltan Somogyi]

2022-04-29 03:12 GMT+10:00 "Zoltan Somogyi" <zoltan.somogyi at runbox.com>:
> For review by anyone. I am particularly seeking feedback
> on the one remaining use of dummy parse trees, which is explained
> in a new long comment in deps_map.m.

Absent at least the promise of a review by then, I intend to commit this
tonight.

Zoltan.