Blacklist test under gcstress.

Test: libcore
Change-Id: I01b7297d3dfeefd769fb68cfb8d3e74e75307b7c
diff --git a/tools/libcore_gcstress_failures.txt b/tools/libcore_gcstress_failures.txt
new file mode 100644
index 0000000..e049cb3
--- /dev/null
+++ b/tools/libcore_gcstress_failures.txt
@@ -0,0 +1,13 @@
+/*
+ * This file contains expectations for ART's buildbot when running gcstress.
+ * The script that uses this file is art/tools/run-libcore-tests.sh.
+ */
+
+[
+{
+  description: "Timeouts on target with gcstress.",
+  result: EXEC_FAILED,
+  modes: [device],
+  names: ["libcore.javax.crypto.CipherBasicsTest#testGcmEncryption"]
+}
+]
diff --git a/tools/run-libcore-tests.sh b/tools/run-libcore-tests.sh
index 6dcc23a..eef74d2 100755
--- a/tools/run-libcore-tests.sh
+++ b/tools/run-libcore-tests.sh
@@ -158,9 +158,12 @@
 fi
 vogar_args="$vogar_args --vm-arg -Xusejit:$use_jit"
 
-# gcstress and debug may lead to timeouts, so we need a dedicated expectations file for it.
-if [[ $gcstress && $debug ]]; then
-  expectations="$expectations --expectations art/tools/libcore_gcstress_debug_failures.txt"
+# gcstress may lead to timeouts, so we need dedicated expectations files for it.
+if [[ $gcstress ]]; then
+  expectations="$expectations --expectations art/tools/libcore_gcstress_failures.txt"
+  if [[ $debug ]]; then
+    expectations="$expectations --expectations art/tools/libcore_gcstress_debug_failures.txt"
+  fi
 fi
 
 # Run the tests using vogar.