Add SE policy for media_metrics

Test: CTS;
Change-Id: Ib9382f2513d8fd0e6812d0157c710d0ad5817231
diff --git a/private/service_contexts b/private/service_contexts
index 502403c..ace9a3a 100644
--- a/private/service_contexts
+++ b/private/service_contexts
@@ -164,6 +164,7 @@
 media.drm                                 u:object_r:mediadrmserver_service:s0
 media.tuner                               u:object_r:mediatuner_service:s0
 media_communication                       u:object_r:media_communication_service:s0
+media_metrics                             u:object_r:media_metrics_service:s0
 media_projection                          u:object_r:media_projection_service:s0
 media_resource_monitor                    u:object_r:media_session_service:s0
 media_router                              u:object_r:media_router_service:s0