[Mirror Layers] Added clone function to layers (1/4)

Added a cloning function to each layer in preparation for mirroring

Test: Nothing to test yet since no calls
Bug: 131622422
Change-Id: Iba0692b75c4d99841de48f40ed55b3dbccf2b9b9
diff --git a/services/surfaceflinger/ContainerLayer.h b/services/surfaceflinger/ContainerLayer.h
index c3624f6..b48d471 100644
--- a/services/surfaceflinger/ContainerLayer.h
+++ b/services/surfaceflinger/ContainerLayer.h
@@ -32,6 +32,9 @@
     bool isVisible() const override;
 
     bool isCreatedFromMainThread() const override { return true; }
+
+protected:
+    sp<Layer> createClone() override;
 };
 
 } // namespace android