Hold only notification info in VoipCallMonitor. am: 9e31e9003d

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/services/Telecomm/+/23115776

Change-Id: I9e8bea22ea72d5a317efe2a12ec1db50afac35fd
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>