Implement Display Layer Stats

Try to collect data for analyzing how many display controller layers we
need and what we use them for. Also part of a bug fixing for potential
memory leak of existing layer tracing work of winscope.

Test: adb shell dumpsys SurfaceFlinger --enable-layer-stats
Test: adb shell dumpsys SurfaceFlinger --disable-layer-stats
Test: adb shell dumpsys SurfaceFlinger --clear-layer-stats
Test: adb shell dumpsys SurfaceFlinger --dump-layer-stats
Bug: b/73668062
Bug: b/74071380
Change-Id: Ie08aa85d34db2c2c767b8e27eb5aad6f7c3fb975
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index b203a7b..9c4f1ce 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -290,6 +290,8 @@
     void writeToProto(LayerProto* layerInfo,
                       LayerVector::StateSet stateSet = LayerVector::StateSet::Drawing);
 
+    void writeToProto(LayerProto* layerInfo, int32_t hwcId);
+
 protected:
     /*
      * onDraw - draws the surface.