Allow adbd to pull /vendor/apex files

These files are required by CTS tests.

Bug: 168540056
Bug: 170202980
Test: ApexSignatureVerificationTest
Change-Id: Ia88517d55003b67efaa94f500e3619bcacc91d80
diff --git a/private/adbd.te b/private/adbd.te
index b95d5dc..6ffe9b6 100644
--- a/private/adbd.te
+++ b/private/adbd.te
@@ -204,6 +204,10 @@
 allow adbd shell:unix_stream_socket { read write shutdown };
 allow adbd shell:fd use;
 
+# Allow pull /vendor/apex files for CTS tests
+allow adbd vendor_apex_file:dir search;
+allow adbd vendor_apex_file:file r_file_perms;
+
 ###
 ### Neverallow rules
 ###