sepolicies for sys prop enabling flag health check

device_config_flags_health_check_prop is used for enabling/disabling
program flags_health_check which is executed during device booting.
"1" means enabling health check actions in flags_health_check, other
values mean flags_health_check will not perform any action.

Test: build succeeded & manual test
Change-Id: I93739dc5d155e057d72d08fd13097eb63c1193b5
diff --git a/private/system_server.te b/private/system_server.te
index d8a67c3..895be0b 100644
--- a/private/system_server.te
+++ b/private/system_server.te
@@ -565,6 +565,11 @@
 # cppreopt property
 set_prop(system_server, cppreopt_prop)
 
+# server configurable flags properties
+# STOPSHIP: Remove the ability for system_server to set property
+# device_config_flags_health_check_prop before release. (b/119627143)
+set_prop(system_server, device_config_flags_health_check_prop)
+
 # BootReceiver to read ro.boot.bootreason
 get_prop(system_server, bootloader_boot_reason_prop)
 # PowerManager to read sys.boot.reason
@@ -892,6 +897,16 @@
 # Only allow crash_dump to connect to system_ndebug_socket.
 neverallow { domain -init -system_server -crash_dump } system_ndebug_socket:sock_file { open write };
 
+# Only allow init, system_server, flags_health_check to set properties for server configurable flags
+neverallow {
+  domain
+  -init
+  -system_server
+  -flags_health_check
+} {
+  device_config_flags_health_check_prop
+}:property_service set;
+
 # system_server should never be executing dex2oat. This is either
 # a bug (for example, bug 16317188), or represents an attempt by
 # system server to dynamically load a dex file, something we do not