### Summary Deleting Project affecting the Merge Requests in the source project ### Steps to reproduce 1. Fork any one project 1. Do some changes and submit MR to the source branch 1. Delete the forked branch 1. Merge Requests will automatically get closed 1. Open the Merge Request that you have submitted to the source branch 1. You will get `500` error ### Example MR I deleted my forked project **`yoginth/gitlab-ce`** (Now I transferred this Project to my Bot Account **`deletece/gitlab-ce-old`**) `https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/28045` https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/28045 ### Output of checks This bug happens on GitLab.com