Fix build with object verification enabled.

Change-Id: I8fa1af738e33a1914ab7c29355a121584edc8c82
diff --git a/src/thread.cc b/src/thread.cc
index ba2919a..940cd88 100644
--- a/src/thread.cc
+++ b/src/thread.cc
@@ -1703,7 +1703,7 @@
 
 void Thread::VerifyStack() {
   UniquePtr<Context> context(Context::Create());
-  ReferenceMapVisitor mapper(GetManagedStack(), context.get(), VerifyObject,
+  ReferenceMapVisitor mapper(GetManagedStack(), GetTraceStack(), context.get(), VerifyObject,
                              Runtime::Current()->GetHeap());
   mapper.WalkStack();
 }