switch maskfilters to sk_sp

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1852113003

Review URL: https://codereview.chromium.org/1852113003
diff --git a/tests/PaintTest.cpp b/tests/PaintTest.cpp
index b07c0e4..253ce86 100644
--- a/tests/PaintTest.cpp
+++ b/tests/PaintTest.cpp
@@ -147,9 +147,8 @@
     // set a few pointers
     SkLayerDrawLooper::Builder looperBuilder;
     paint.setLooper(looperBuilder.detach());
-    SkMaskFilter* mask = SkBlurMaskFilter::Create(kNormal_SkBlurStyle,
-                                      SkBlurMask::ConvertRadiusToSigma(SkIntToScalar(1)));
-    paint.setMaskFilter(mask)->unref();
+    paint.setMaskFilter(SkBlurMaskFilter::Make(kNormal_SkBlurStyle,
+                                               SkBlurMask::ConvertRadiusToSigma(1)));
 
     // copy the paint using the copy constructor and check they are the same
     SkPaint copiedPaint = paint;