Set visibility in world outliner reset when project is reopened

If visibility is altered in world outliner, the visibility will be reset upon closing and re-opening the project.

1. Open Editor (any project)
2. In scene outliner, set some actors to hidden by pressing the eye icon
3. Save, close, reopen project

Results:

All actors are set to visible.

Expected:

Actors set to hidden are still hidden.

[4.8.3] Editor not saving actor visibility in world outliner