grsummary: handle hggit guest repos
Created originally on Bitbucket by sietsebb (Sietse Brouwer)
Changesets for this Pull Request have not been imported, because it had been already declined on Bitbucket. Marked as closed by the import user.
grsummary looked for draft commits to see if a repo had outgoing
changes, but hggit guests [1] consist entirely of drafts, and so always
looked unpushed. Now grsummary checks if the guest is an hggit repo; if
it is, unpushed commits are found with the revset not(fromgit()),
instead.