Merge "Have a method to stop VPN and send event to VPN app" am: 4e08dae7d2 am: e3325d736a

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/2194337

Change-Id: I08276ff4885f12e9273bb4ef310ec32c26c53409
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>