Add another failure for libcore/gcstress/debug.

Test: run-libcore-tests.sh
Change-Id: Ic7077e0701326c604ec2dfaec397efaaac7c71fb
diff --git a/tools/libcore_gcstress_debug_failures.txt b/tools/libcore_gcstress_debug_failures.txt
index c0ebda1..4e10d91 100644
--- a/tools/libcore_gcstress_debug_failures.txt
+++ b/tools/libcore_gcstress_debug_failures.txt
@@ -39,6 +39,7 @@
           "jsr166.StampedLockTest#testReadTryLock_Interruptible",
           "jsr166.StampedLockTest#testReadLockInterruptibly_Interruptible",
           "jsr166.StampedLockTest#testReadLockInterruptibly",
+          "jsr166.StampedLockTest#testWriteLockInterruptibly",
           "org.apache.harmony.tests.java.lang.ProcessManagerTest#testSleep"
   ]
 },