Merge "Revert^2 "Track last known RAT in voice call."" into tm-qpr-dev am: e50fd722

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/opt/telephony/+/20180495



Change-Id: I37a97a7116e6778da618353092e8d8bb9a2e1f7f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>