Child Actor Component Not Destroyed When Parent BP Is Replaced in Scene

Having an actor in the level with a child actor component, replacing it with another copy of itself, and deleting the copy results in a Child Actor remaining in the world outliner, which cannot be deleted. This actor does not appear in the scene, and cannot be selected.

Occcurs in 4.8.3, 4.9.2, and Main CL 2731616.

1. Open the editor
2. Create new Blueprint derived from Actor
3. Add Child Actor Component
4. Set the Child Actor Components Class to Actor
5. Populate NewBlueprint in scene
6. Observe "ActorXX" in World Outliner (this is the child actor component)
7. Select NewBlueprint in the scene
8. Right click on NewBlueprint in the scene and select "Replace Selected Actors with" New Blueprint
9. Observe two instances of "ActorXX" in World Outliner
10. Delete NewBlueprint from scene
11. Observe remaining "ActorXX" in World Outliner
12. Attempt to delete

Result: Child Actor from the first instance of New Blueprint remains in the world outliner and is unable to be deleted.

Expected: The Child Actor from the original (before you replace it) blueprint would be removed when you used Replace Selected Actors With.