Make thread dumping more tolerant of broken invariants during abort.

Change-Id: Ie1bc20debe72f2ea2bf4c1be50cd9877c823670a
diff --git a/runtime/barrier.cc b/runtime/barrier.cc
index b8edad3..5a8fbb3 100644
--- a/runtime/barrier.cc
+++ b/runtime/barrier.cc
@@ -23,7 +23,7 @@
 
 Barrier::Barrier(int count)
     : count_(count),
-      lock_("GC barrier lock"),
+      lock_("GC barrier lock", kThreadSuspendCountLock),
       condition_("GC barrier condition", lock_) {
 }