partial switch over to sp usage of shaders

gm/circles.cpp

Index: gm/circles.cpp
diff --git a/gm/circles.cpp b/gm/circles.cpp
index 369548cc5996d878aad3568dc818bd805b2a5fa5..4d3e33daee5aab875b025394984668ba33b923de 100644
--- a/gm/circles.cpp
+++ b/gm/circles.cpp
@@ -67,13 +67,8 @@ protected:
         SkPoint center = SkPoint::Make(SkIntToScalar(40), SkIntToScalar(40));
         SkColor colors[] = { SK_ColorBLUE, SK_ColorRED, SK_ColorGREEN };
         SkScalar pos[] = { 0, SK_ScalarHalf, SK_Scalar1 };
-        SkShader* s = SkGradientShader::CreateRadial(center,
-                                                     SkIntToScalar(20),
-                                                     colors,
-                                                     pos,
-                                                     SK_ARRAY_COUNT(colors),
-                                                     SkShader::kClamp_TileMode);
-        p.setShader(s)->unref();
+        p.setShader(SkGradientShader::MakeRadial(center, 20, colors, pos, SK_ARRAY_COUNT(colors),
+                                                 SkShader::kClamp_TileMode));
         fPaints.push_back(p);
         }