Merge "Move Tether4Key and Tether4Value to common libs" am: 34e16b9537 am: a1349ad262

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1978067

Change-Id: I0c0571a7a4cbd50d0e8be196885d191e923b8a4c