[TimeStats] Track RenderEngine time per frame.

Bug: 144037240
Test: dumpsys SurfaceFlinger --timestats -dump
Change-Id: I7a4dd680ed08e3a7a05e3fd08d5e133e9d394193
diff --git a/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h b/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
index 94fc5f7..e05e7a5 100644
--- a/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
+++ b/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
@@ -189,6 +189,10 @@
                 std::make_unique<impl::HWComposer>(std::move(composer)));
     }
 
+    void setupTimeStats(const std::shared_ptr<TimeStats>& timeStats) {
+        mFlinger->mCompositionEngine->setTimeStats(timeStats);
+    }
+
     void setupScheduler(std::unique_ptr<DispSync> primaryDispSync,
                         std::unique_ptr<EventControlThread> eventControlThread,
                         std::unique_ptr<EventThread> appEventThread,