Track untrusted_app_27 SELinux denial

vrcore is trying to access external storage before
it is available.

Bug: 118185801
Test: n/a
Change-Id: Ieb38a1bfb977d9f6f642fecdd1000a195b2c8259
diff --git a/private/bug_map b/private/bug_map
index b9c5b8c..ae7b695 100644
--- a/private/bug_map
+++ b/private/bug_map
@@ -28,6 +28,7 @@
 system_server sdcardfs file 77856826
 system_server storage_stub_file dir 112609936
 system_server zygote process 77856826
+untrusted_app_27 mnt_user_file dir 118185801
 usbd usbd capability 72472544
 vrcore_app mnt_user_file dir 118185801
 webview_zygote system_data_file lnk_file 123246126