Revert of more shader-->sp conversions

gm/matrixconvolution.cpp

Index: gm/matrixconvolution.cpp
diff --git a/gm/matrixconvolution.cpp b/gm/matrixconvolution.cpp
index b02f743f2933321cc38f27bb7d5dddf68eaa693c..3b159f455bd084df5255f3b4dcff62ad01d46030 100644
--- a/gm/matrixconvolution.cpp
+++ b/gm/matrixconvolution.cpp
@@ -37,8 +37,8 @@
                            SkPoint::Make(0, SkIntToScalar(80)) };
         SkColor colors[2] = { 0xFFFFFFFF, 0x40404040 };
         SkScalar pos[2] = { 0, SkIntToScalar(80) };
-        paint.setShader(SkGradientShader::MakeLinear(
-            pts, colors, pos, 2, SkShader::kClamp_TileMode));
+        paint.setShader(SkGradientShader::CreateLinear(
+            pts, colors, pos, 2, SkShader::kClamp_TileMode))->unref();
         const char* str = "e";
         canvas.drawText(str, strlen(str), SkIntToScalar(-10), SkIntToScalar(80), paint);
     }