debugdiscovery: include the number of heads in all sets
We already displayed information about heads of the common set that are either
local or remote heads. We now also do so for heads of the common set that are
both local and remote heads too. This is useful because various step in the
set discovery algorithm have head specific optimizations.
Our full contribution guidelines are in our wiki, please see:
https://www.mercurial-scm.org/wiki/ContributingChanges
If you just want a checklist to follow, you can go straight to
https://www.mercurial-scm.org/wiki/ContributingChanges#Submission_checklist
If you can't run the entire testsuite for some reason (it can be
difficult on Windows), please at least run `contrib/check-code.py` on
any files you've modified and run `python contrib/check-commit` on any
commits you've made (for example, `python contrib/check-commit
273ce12ad8f1` will report some style violations on a very old commit).