reland: untrusted_app_29: add new targetSdk domain

Enforce new requirements on app with targetSdkVersion=30 including:
- No RTM_GETLINK on netlink route sockets.

Remove some of the repetitive descriptions in each untrusted_app_N.te
file, and instead refer to the description in
public/untrusted_app.te.

Bug: 141455849
Test: CtsSelinuxTargetSdkCurrentTestCases
Test: libcore.java.net.NetworkInterfaceTest#testGetNetworkInterfaces
Change-Id: I89553e48db3bc71f229c71fafeee9005703e5c0b
diff --git a/private/seapp_contexts b/private/seapp_contexts
index 3838578..fed4325 100644
--- a/private/seapp_contexts
+++ b/private/seapp_contexts
@@ -163,7 +163,8 @@
 user=_app isPrivApp=true name=com.google.android.gms domain=gmscore_app type=privapp_data_file levelFrom=user
 user=_app isPrivApp=true name=com.google.android.gms.* domain=gmscore_app type=privapp_data_file levelFrom=user
 user=_app isPrivApp=true name=com.google.android.gms:* domain=gmscore_app type=privapp_data_file levelFrom=user
-user=_app minTargetSdkVersion=29 domain=untrusted_app type=app_data_file levelFrom=all
+user=_app minTargetSdkVersion=30 domain=untrusted_app type=app_data_file levelFrom=all
+user=_app minTargetSdkVersion=29 domain=untrusted_app_29 type=app_data_file levelFrom=all
 user=_app minTargetSdkVersion=28 domain=untrusted_app_27 type=app_data_file levelFrom=all
 user=_app minTargetSdkVersion=26 domain=untrusted_app_27 type=app_data_file levelFrom=user
 user=_app domain=untrusted_app_25 type=app_data_file levelFrom=user