switch maskfilters to sk_sp

gm/drawbitmaprect.cpp

Index: gm/drawbitmaprect.cpp
diff --git a/gm/drawbitmaprect.cpp b/gm/drawbitmaprect.cpp
index 7d830475fa314431ca3f10e007c1c37bcd7bb77f..bd6fffec6376b7de2b38df815cc644a14a91f5df 100644
--- a/gm/drawbitmaprect.cpp
+++ b/gm/drawbitmaprect.cpp
@@ -211,12 +211,11 @@ protected:
             paint.setFilterQuality(kLow_SkFilterQuality);
 
             srcRect.setXYWH(1, 1, 3, 3);
-            SkMaskFilter* mf = SkBlurMaskFilter::Create(
+            paint.setMaskFilter(SkBlurMaskFilter::Make(
                 kNormal_SkBlurStyle,
                 SkBlurMask::ConvertRadiusToSigma(SkIntToScalar(5)),
                 SkBlurMaskFilter::kHighQuality_BlurFlag |
-                SkBlurMaskFilter::kIgnoreTransform_BlurFlag);
-            paint.setMaskFilter(mf)->unref();
+                SkBlurMaskFilter::kIgnoreTransform_BlurFlag));
             canvas->drawBitmapRect(bm, srcRect, dstRect, &paint);
         }
     }