Merge "Handle ringback changes between call state changes." into sc-dev am:...

Merge "Handle ringback changes between call state changes." into sc-dev am: 632f4e1a am: b04928c6 am: 66054389

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/opt/telephony/+/15029523

Change-Id: Ib7658b8931362f7c6c161f966984a643d27397b6