Most methods of RepositoryService are of the global type (create etc.), but not this one. This is perhaps the only method we could have been needing for %"HGitaly1: Hg SHAs", but I've replaced its call by a conversion to Git and back in the run to working MRs after heptapod#364. We won't wait until all methods of RepositoryService are ready for this one to be called.