Reorder ART's `OWNERS` file.

Automatically filed bugs for broken tests now only pick the first
ten e-mail addresses from an `OWNERS` file when CC-ing test
owners on newly filed bugs. Move Core Libraries members at the
end of ART's `OWNERS` file, as bugs filed for ART test should be
looked at by ART members first.

Test: Rely on TreeHugger/AyeAye
Test: build/make/tools/checkowners.py -c art/OWNERS
Change-Id: I90ab0ec8c102b93b9bbc69e75d8964c40fc43797
diff --git a/OWNERS b/OWNERS
index 06c7d08..cfaa94b 100644
--- a/OWNERS
+++ b/OWNERS
@@ -4,16 +4,18 @@
 jiakaiz@google.com
 lokeshgidra@google.com
 mast@google.com
-miguelaranda@google.com
-mingaleev@google.com
 mythria@google.com
 ngeoffray@google.com
+rpl@google.com
+solanes@google.com
+vmarko@google.com
+
+# Core Libraries.
+miguelaranda@google.com
+mingaleev@google.com
 nikitai@google.com
 oth@google.com
 prb@google.com
-rpl@google.com
 skvadrik@google.com
-solanes@google.com
 sorinbasca@google.com
 vichang@google.com
-vmarko@google.com