Merge "Null phone check when checking if radio is off for thermal mitigation." into sc-qpr1-dev am: 070541b7cc am: da9d42b538 am: 1f263aa781

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/services/Telephony/+/15531684

Change-Id: Ibbeffdedbfc6f0517d7b7eec4a66db8720dcc174