Update standby firewall rules when an app came out of standby mode.

Fixes: 64690559
Test: cts-tradefed run singleCommand cts-dev --module CtsHostsideNetworkTests -t \
      com.android.cts.net.HostsideRestrictBackgroundNetworkTests
Test: bit FrameworksServicesTests:com.android.server.net.ConnOnActivityStartTest

Change-Id: If437047a3b9e37ca7c587460d39f93ce4d4febcd