Inform Application thread to block for network rules to be updated. am: ffa1d57d

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17587700



Change-Id: Ia19bad0279f0412771754497334c59950bfbc4aa
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>