Hide overlay windows when showing phone account enable/disable screen. am: a7d57ace58

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/services/Telecomm/+/20069028

Change-Id: I38438cf30a61b4fdc9f7d57bc69f9054c8d309f5
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>