When I added change descriptions and diffsets to the draft deletion handler, I wasn't thinking about how we delete the draft after publishing it. In that case, we've assigned the change description to the review request, and assigned the diffset to the history, but we haven't cleared them from the draft object. We were therefore deleting the data right after we published it. This change fixes that up to properly check that those objects are no longer alive. Unit tests have been added for this case with both of those as well as file attachments, which didn't have this same problem because of the way we calculate the file attachment state. Testing Done: - Ran unit tests. - Published a new review request that included a diff and saw that my diff wasn't immediately deleted.