Read APPS_ALLOWED_ON_RESTRICTED_NETWORKS setting from PermissionMonitor

Let PermissionMonitor read APPS_ALLOWED_ON_RESTRICTED_NETWORKS
setting and grant netd system permission to uids whose package
name is listed in setting.

Bug: 185149952
Test: atest FrameworksNetTests
Merged-In: I856b545c0339a262abbe9d432cfda125bc82dc12
(clean cherry-pick)

Change-Id: I856b545c0339a262abbe9d432cfda125bc82dc12