switch maskfilters to sk_sp

gm/texteffects.cpp

Index: gm/texteffects.cpp
diff --git a/gm/texteffects.cpp b/gm/texteffects.cpp
index 5962cd7f16f714f148225646adb3301aba87506c..a398ae2e6895e00ca0899939cfbdf3b7ec642dfb 100644
--- a/gm/texteffects.cpp
+++ b/gm/texteffects.cpp
@@ -13,8 +13,8 @@
 #include "SkLayerRasterizer.h"
 
 static void r0(SkLayerRasterizer::Builder* rastBuilder, SkPaint& p) {
-    p.setMaskFilter(SkBlurMaskFilter::Create(kNormal_SkBlurStyle,
-                              SkBlurMask::ConvertRadiusToSigma(SkIntToScalar(3))))->unref();
+    p.setMaskFilter(SkBlurMaskFilter::Make(kNormal_SkBlurStyle,
+                                           SkBlurMask::ConvertRadiusToSigma(SkIntToScalar(3))));
     rastBuilder->addLayer(p, SkIntToScalar(3), SkIntToScalar(3));
 
     p.setMaskFilter(nullptr);