This test catch the regression introduced in r.android.com/1432958.
Bug: 1432958
Test: atest TetheringTest
Change-Id: Id0c1afb5563954ffee1f598a3a5de6a245d77a0e
Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1459889
Change-Id: Ie80d4d5d535d70df493cad0a80166d779bc6ab77
Merged-In: Id0c1afb5563954ffee1f598a3a5de6a245d77a0e
(cherry picked from commit c46006da45)