Fix object verification.

Refactor VERIFY_OBJECT_ENABLED to become less brittle to change enum and global
constant.

Change-Id: Ie405106be81dce9a913730c7f46a5659582fa18b
diff --git a/src/thread-inl.h b/src/thread-inl.h
index 414b8d8..6c1ae59 100644
--- a/src/thread-inl.h
+++ b/src/thread-inl.h
@@ -124,6 +124,13 @@
   return static_cast<ThreadState>(old_state);
 }
 
+inline void Thread::VerifyStack() {
+  Heap* heap = Runtime::Current()->GetHeap();
+  if (heap->IsObjectValidationEnabled()) {
+    VerifyStackImpl();
+  }
+}
+
 }  // namespace art
 
 #endif  // ART_SRC_THREAD_INL_H_