Expose core-test-rules to CTS CloseGuardTest

Needed to test public API android.util.CloseGuard.
Note that dalvik.system.CloseGuard is already tested
in CtsLibcoreTestCases.

Bug: 150692734
Test: atest CloseGuardTest
Change-Id: Ieac08c9b9f0556bbffc24491cb56a009074da00c
diff --git a/JavaLibrary.bp b/JavaLibrary.bp
index d35fd04..1be8711 100644
--- a/JavaLibrary.bp
+++ b/JavaLibrary.bp
@@ -493,6 +493,7 @@
         "//frameworks/base/location/tests/locationtests",
         "//frameworks/base/core/tests/coretests",
         "//frameworks/base/wifi/tests",
+        "//cts/tests/tests/util",
     ],
     hostdex: true,
     srcs: [