PermissionMonitor only saves netd network permissions by appId.
Then apply same permision to uids which are same appId. But
UIDS_ALLOWED_ON_RESTRICTED_NETWORKS can allow single uid has
restricted network permission. Thus, save the netd network
permissions by uid that can apply different permission to each
uid.

Bug: 192431153
Test: atest FrameworksNetTests
Change-Id: I942cbe0fa30758a7497c47a1b684ed70c4e3b09e