partial switch over to sp usage of shaders

gm/colorfilters.cpp

Index: gm/colorfilters.cpp
diff --git a/gm/colorfilters.cpp b/gm/colorfilters.cpp
index dcd24d9ce431536dbcd1a84b319985de86f5edb4..eaee39dd55b729df124a2e7fc1b3f58a27059e2d 100644
--- a/gm/colorfilters.cpp
+++ b/gm/colorfilters.cpp
@@ -10,7 +10,7 @@
 #include "SkColorMatrixFilter.h"
 #include "SkGradientShader.h"
 
-static SkShader* make_shader(const SkRect& bounds) {
+static sk_sp<SkShader> make_shader(const SkRect& bounds) {
     const SkPoint pts[] = {
         { bounds.left(), bounds.top() },
         { bounds.right(), bounds.bottom() },
@@ -19,9 +19,8 @@ static SkShader* make_shader(const SkRect& bounds) {
         SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorBLACK,
         SK_ColorCYAN, SK_ColorMAGENTA, SK_ColorYELLOW,
     };
-    return SkGradientShader::CreateLinear(pts,
-                                          colors, nullptr, SK_ARRAY_COUNT(colors),
-                                          SkShader::kClamp_TileMode);
+    return SkGradientShader::MakeLinear(pts, colors, nullptr, SK_ARRAY_COUNT(colors),
+                                        SkShader::kClamp_TileMode);
 }
 
 typedef void (*InstallPaint)(SkPaint*, uint32_t, uint32_t);
@@ -53,7 +52,7 @@ protected:
         SkPaint paint;
         SkRect r;
         r.setWH(600, 50);
-        paint.setShader(make_shader(r))->unref();
+        paint.setShader(make_shader(r));
 
         const struct {
             InstallPaint    fProc;