Make NetworkStack API shims available to Tethering. am: 0ef45d4c5d am: 7bd1cb75dc am: ffeef17f80

Original change: https://android-review.googlesource.com/c/platform/packages/modules/NetworkStack/+/1614992

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: Iee1ca12549bdef8ae2980d1e87bcf8206f5b4a06