am b654e6e5: am d144748d: Merge "Add missing include"

* commit 'b654e6e55a3e8d7e8c2e0b8b1ff4bb4f76c10e05':
  Add missing include
diff --git a/include/utils/RefBase.h b/include/utils/RefBase.h
index d92cfb0..0af7e6a 100644
--- a/include/utils/RefBase.h
+++ b/include/utils/RefBase.h
@@ -115,6 +115,7 @@
     // used to override the RefBase destruction.
     class Destroyer {
         friend class RefBase;
+        friend class weakref_type;
     public:
         virtual ~Destroyer();
     private: