[TimeStats] Track RenderEngine time per frame.

Bug: 144037240
Test: dumpsys SurfaceFlinger --timestats -dump
Change-Id: I7a4dd680ed08e3a7a05e3fd08d5e133e9d394193
diff --git a/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp b/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp
index bac7c75..8db8fd4 100644
--- a/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp
+++ b/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp
@@ -656,10 +656,14 @@
                 .WillRepeatedly(Return(&mOutputLayer2));
         EXPECT_CALL(mOutput, getCompositionEngine()).WillRepeatedly(ReturnRef(mCompositionEngine));
         EXPECT_CALL(mCompositionEngine, getRenderEngine()).WillRepeatedly(ReturnRef(mRenderEngine));
+        EXPECT_CALL(mCompositionEngine, getTimeStats())
+                .WillRepeatedly(ReturnRef(*mTimeStats.get()));
     }
 
     StrictMock<mock::CompositionEngine> mCompositionEngine;
     StrictMock<renderengine::mock::RenderEngine> mRenderEngine;
+    // TODO: make this is a proper mock.
+    std::shared_ptr<TimeStats> mTimeStats = std::make_shared<android::impl::TimeStats>();
     mock::DisplayColorProfile* mDisplayColorProfile = new StrictMock<mock::DisplayColorProfile>();
     mock::RenderSurface* mRenderSurface = new StrictMock<mock::RenderSurface>();
     StrictMock<mock::OutputLayer> mOutputLayer1;