diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 1349bec..bde1a8e 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -316,6 +316,9 @@
     friend class BufferLayer;
     friend class MonitoredProducer;
 
+    // For unit tests
+    friend class TestableSurfaceFlinger;
+
     // This value is specified in number of frames.  Log frame stats at most
     // every half hour.
     enum { LOG_FRAME_STATS_PERIOD =  30*60*60 };