SF TimeStats: Make TimeStats class non-singleton

Bug: 119290000
Test: atest libsurfaceflinger_unittest:TimeStatsTest
Change-Id: I725a880506b0c0df14802db4bc38524ab4cf1ead
diff --git a/services/surfaceflinger/SurfaceFlingerFactory.h b/services/surfaceflinger/SurfaceFlingerFactory.h
index 496bbf0..1c27cc7 100644
--- a/services/surfaceflinger/SurfaceFlingerFactory.h
+++ b/services/surfaceflinger/SurfaceFlingerFactory.h
@@ -44,6 +44,7 @@
 class StartPropertySetThread;
 class SurfaceFlinger;
 class SurfaceInterceptor;
+class TimeStats;
 
 struct DisplayDeviceCreationArgs;
 struct LayerCreationArgs;
@@ -82,6 +83,8 @@
     virtual sp<ColorLayer> createColorLayer(const LayerCreationArgs& args) = 0;
     virtual sp<ContainerLayer> createContainerLayer(const LayerCreationArgs& args) = 0;
 
+    virtual std::unique_ptr<TimeStats> createTimeStats() = 0;
+
 protected:
     ~Factory() = default;
 };