Update canCreateSystemApplicationOverlay when adding system overlays

Ensure the permission state is properly updated when adding overlay
windows. This prevents the Session state to get outdated and policies to
get enforced when they shouldn't.

Test: manual
Bug: 429985912
Flag: com.android.media.projection.flags.recording_overlay
Change-Id: Ic436e853b1336796d9548589586bb364a6946fb1