After Undo/Redo for ObservableList, its inspector doesn't repaint to show its current state

1. Create TrackedAlias and inspect it
2. Create a camera rig (e.g. oculus intergration camera rig)
3. Add the camera rig into TrackedAlias Camera Rigs array
4. ctrl-z to undo
5. expected behaviour: the inspector shows the camera rigs array is empty (size 0)
6. current behaviour: the inspector still show the camera rig is in the array (size 1). when deselect and select the TrackedAlias again, the array is empty (size 0)
8. ctrl-y to redo
9. similar to undo, the redo also show the incorrect array