Merge "Move TetherStatsKey and TetherStatsValue to common libs" am: 8315d1cf03 am: 00882a40a6

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2054166

Change-Id: Ia523e919734f96e23e543740942fedc00d0068e0
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>