Showing wrong exceeding value on push when rejected

Summary

When trying to push a file to LFS and it exceeds the repository size limit, we get this:

batch response: http: Your push has been rejected, because this repository has exceeded its size limit of 40 MB by -2193050 Bytes. Please contact your GitLab administrator for more information.

After some debugging, I've found that we calculate it correctly on LfsRequest#objects_exceed_repo_limit?, but when showing the error message on Gitlab::RepositorySizeError, we use project#repository_and_lfs_size, that rely on ProjectStatistics#lfs_objects_size which is 0 at this point, because we still don't have this size persisted yet.

Steps to reproduce

• Change the size limit of a project to a value close to being exceeded (e.g.: If the repo has 30mb, change the repository size limit to 35mb)
• Push a file to LFS that will exceed 35mb
  • git lfs track file.rar
  • git push origin test-limit-branch

Expected behavior

The correct value that exceeds the limit. If the limit is 40MB, we're already using 35MB and we push a 10MB file, we should get:

batch response: http: Your push has been rejected, because this repository has exceeded its size limit of 40 MB by 5 MB. Please contact your GitLab administrator for more information.

Actual behavior

batch response: http: Your push has been rejected, because this repository has exceeded its size limit of 40 MB by -2193050 Bytes. Please contact your GitLab administrator for more information.

cc @rymai @smcgivern

Good catch @oswaldo!

added ~978335 label

changed milestone to %8.17

added regression label

assigned to @oswaldo

mentioned in merge request !1105 (merged)

closed via merge request !1105 (merged)

mentioned in commit 3685aa65