Add fold state to voice call session am: 65debc1e am: 11d646ee

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/opt/telephony/+/23214365



Change-Id: I703651732f59ed595920653ed07c6280c494b31e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>