Merge "Adding Tethering proto" am: 075dd6f8ff am: d00d76568e am: 444446bc34

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2024488

Change-Id: Ie9ce38ec67e00e89452e08a27335d297f80dc9d7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>