How to reproduce:
1. Create a new Unity project
2. Create a GameObject and add an Animator component
3. Create a Prefab out of that GameObject
4. Remove the Animator Component from the Prefab instance
5. Add another Animator Component to the Prefab instance
6. Attempt to revert the removed Animator Component
7. Remove the later added Animator Component from the Prefab instance
8. Attempt to revert the original Animator Component again

Expected result: the removed Animator Component is reverted successfully
Actual result: nothing happens. There are no Overrides (Can be checked by pressing "Overrides" button), but the Removed Animator is still visible (and can be applied from context menu) in Inspector.

Reproducible with: 2018.4.22f1, 2019.3.11f1, 2020.1.0b6, 2020.2.0a8
Not reproducible with: 2017.4.40f1(uses the old Prefab system)

Notes:
Issue occurs with all Components that can only be added once