switch maskfilters to sk_sp

bench/RectoriBench.cpp

Index: bench/RectoriBench.cpp
diff --git a/bench/RectoriBench.cpp b/bench/RectoriBench.cpp
index e2a44e383f6aa69e5b3b5a654e6fdd9d5d19e4fa..ad3d4c29ea807bb53bb66389ded96f576883d356 100644
--- a/bench/RectoriBench.cpp
+++ b/bench/RectoriBench.cpp
@@ -86,10 +86,8 @@ private:
 
         SkPaint* paint = looperBuilder.addLayer(info);
 
-        SkMaskFilter* mf = SkBlurMaskFilter::Create(kNormal_SkBlurStyle,
-                                                    sigma,
-                                                    SkBlurMaskFilter::kHighQuality_BlurFlag);
-        paint->setMaskFilter(mf)->unref();
+        paint->setMaskFilter(SkBlurMaskFilter::Make(kNormal_SkBlurStyle, sigma,
+                                                    SkBlurMaskFilter::kHighQuality_BlurFlag));
 
         //-----------------------------------------------
         info.fPaintBits = 0;