Blacklist test in right expectation file.

bug:70958370
Change-Id: I1b989db5cab27d77555926c3fa753655790c2d2b
diff --git a/tools/external_oj_libjdwp_art_failures.txt b/tools/external_oj_libjdwp_art_failures.txt
index c96830a..828c0aa 100644
--- a/tools/external_oj_libjdwp_art_failures.txt
+++ b/tools/external_oj_libjdwp_art_failures.txt
@@ -59,6 +59,13 @@
   name: "org.apache.harmony.jpda.tests.jdwp.ObjectReference.IsCollectedTest#testIsCollected001"
 },
 {
+  description: "Test is flaky",
+  result: EXEC_FAILED,
+  bug: 70958370,
+  names: [ "org.apache.harmony.jpda.tests.jdwp.ObjectReference.EnableCollectionTest#testEnableCollection001",
+           "org.apache.harmony.jpda.tests.jdwp.MultiSession.EnableCollectionTest#testEnableCollection001" ]
+},
+{
   description: "Test crashes",
   result: EXEC_FAILED,
   bug: 69591477,