Audit access to libart

Grant access to all processes and audit access. The end goal is to
whitelist all access to the interpreter. Several processes including
dex2oat, apps, and zygote were observed using libart, so omit them
from auditing and explicitly grant them access.

Test: Angler builds and boots

Bug: 29795519
Change-Id: I9b93c7dbef5c49b95a18fd26307955d05a1c8e88
diff --git a/file_contexts b/file_contexts
index eeda6c7..33b628a 100644
--- a/file_contexts
+++ b/file_contexts
@@ -216,7 +216,8 @@
 /system/bin/update_engine        u:object_r:update_engine_exec:s0
 /system/bin/bspatch              u:object_r:update_engine_exec:s0
 /system/bin/hw/wifi_hal_legacy   u:object_r:wifi_hal_legacy_exec:s0
-
+/system/fake-lib(64)?/libart.*   u:object_r:libart_file:s0
+/system/lib(64)?/libart.*        u:object_r:libart_file:s0
 
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 # Vendor files