BUG: Categorical.sort_values inplace breaking views
- [ ] closes #xxxx
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

this doesn't have any user facing appearances rigth? > this doesn't have any user facing appearances rigth?

Only if a user was using Categorical.sort_values directly