We were still having issues with this function when taking the positive
branch, when predicates cause many matches within tables. This was causing
us to hit stack limits in certain browsers on the Summary Page.
This converts it to an iterator so that all branches are tail-recursive, and
then enables TCO on them.
I was disappointed to find that there's little performance or memory benefit
in running our test suite.
Mike Gerwitz
8ce217f779