Fix damage tracking for RenderNode drawn twice

Bug: 127866048
Test: CustomRenderer demo
Change-Id: I431a7284b1d0a026e06500a78f41830a268235a5
diff --git a/libs/hwui/RenderNode.h b/libs/hwui/RenderNode.h
index 6060123..23e7a0e 100644
--- a/libs/hwui/RenderNode.h
+++ b/libs/hwui/RenderNode.h
@@ -255,6 +255,8 @@
     DisplayList* mDisplayList;
     DisplayList* mStagingDisplayList;
 
+    int64_t mDamageGenerationId;
+
     friend class AnimatorManager;
     AnimatorManager mAnimatorManager;