Merge "Improve carrier id testability" am: d4d2391c9c am: eac2933f40 am: db7f99a8fe

Original change: https://android-review.googlesource.com/c/platform/packages/providers/TelephonyProvider/+/1347084

Change-Id: Idfbd81ae7dfb71f964de208dc32d2fb7c1414a26