* Draft: Fix AnnotationStyleEditor delete last style error
Fixes#17716.
* Fix rename problem as well
The on_rename function should update self.current_style as well. To avoid this scenario:
1. Create style A.
2. Create style B.
3. Rename style B to C.
4. Switch to style A.
5. Press OK.
6. Start the tool again.
7. Result: there are 3 styles A, B and C.