Update sepolicy with new native boot flag for activity_manager

Whitelist the persistent system properties that will be used as
flags in activity manager experiments.

Bug: 120794810
Test: m, flash, test getting flag value in ActivityManagerService.java
Change-Id: I90a10bc87d6db3a64347b62fd02e6f0b12ac9fa8
diff --git a/private/property_contexts b/private/property_contexts
index d7563bc..3296a04 100644
--- a/private/property_contexts
+++ b/private/property_contexts
@@ -168,6 +168,7 @@
 
 # Properties that relate to server configurable flags
 device_config.reset_performed           u:object_r:device_config_reset_performed_prop:s0
+persist.device_config.activity_manager_native_boot. u:object_r:device_config_activity_manager_native_boot_prop:s0
 persist.device_config.attempted_boot_count        u:object_r:device_config_boot_count_prop:s0
 persist.device_config.input_native_boot. u:object_r:device_config_input_native_boot_prop:s0
 persist.device_config.netd_native.           u:object_r:device_config_netd_native_prop:s0