Fix for empty saveLayer() with a filter which affects transparent black.

src/core/SkPictureRecord.h

Index: src/core/SkPictureRecord.h
diff --git a/src/core/SkPictureRecord.h b/src/core/SkPictureRecord.h
index 0f0986fba748b83768522f2e5de1d02d6f5fd22d..22d2546072d7d31923c9a0a501d195141b4cd881 100644
--- a/src/core/SkPictureRecord.h
+++ b/src/core/SkPictureRecord.h
@@ -89,6 +89,9 @@ public:
         fOptsEnabled = optsEnabled;
     }
 
+protected:
+    void addNoOp();
+
 private:
     void handleOptimization(int opt);
     size_t recordRestoreOffsetPlaceholder(SkRegion::Op);