few fixes

* actually complete renaming the private 'user_qv' and 'redirect_qv' instance vars
  * they were renamed from `qv_user` and `qv_redirect` to `user_qv` and `redirect_qv`
* call bstat's own `get_current_user_id()` function

see https://github.com/GigaOM/legacy-pro/issues/3168