Fix: VPNs update caps upon underlying network disconnect.

Clean cherry-pick of ag/4083954

Bug: 79748782
Test: ConnectivityServiceTests still pass
Change-Id: I21e866c723099e5c3dee54ff13e830d44427fc7a
Merged-In: I12c948ebeb2b74290908f8320ff77220dc4a9fb9
2 files changed