Views cache tags are not invalidated after deleting an image style.

Follow-up to #2479487: ImageStyles can be deleted while having dependent configuration. Not caused by this issue, only related in that I found this bug while testing this issue.

Cache tags are not invalidated after deleting an image style.

Another possible issue title: ImageStyles can be deleted while views fields have dependent configuration.

1. Create a view page
2. Add an image field
3. Set the image stlye
4. Delete that image style
5. Go to the view page
6. Fatal error: Call to a member function getCacheTags() on null in /d8/core/modules/image/src/Plugin/Field/FieldFormatter/ImageFormatter.php on line 198