Attempting to use the API endpoint
/projects/:id/repository/tree?recursive=true would only return a subset
of the results since the full recursive list wasn't actually being
returned.
Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/61979
The Rugged implementation was recursively scanning the repository to
create `flat_path` because the post-process step was being called from
with a loop. For large repositories, this was significantly slowing
things down. Break the call to `rugged_populate_flat_path` out of this
loop to make this work efficiently.
Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/59759