Reland of "Finish conversion to sk_sp<SkShader> (patchset #2 id:20001 of https://codereview.chromium.org/1803763002/ )"

This reverts commit 106e10ddff5d473dc81dd1ce8ade615585ea609b.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1803783002
CQ_EXTRA_TRYBOTS=client.skia.compile:Build-Ubuntu-GCC-x86_64-Release-CMake-Trybot,Build-Mac-Clang-x86_64-Release-CMake-Trybot

TBR=

Review URL: https://codereview.chromium.org/1803783002
diff --git a/bench/ImageFilterCollapse.cpp b/bench/ImageFilterCollapse.cpp
index 2a2fa3a..bd3f80f 100644
--- a/bench/ImageFilterCollapse.cpp
+++ b/bench/ImageFilterCollapse.cpp
@@ -66,10 +66,8 @@
             SK_ColorBLACK, SK_ColorGREEN, SK_ColorCYAN,
             SK_ColorRED, 0, SK_ColorBLUE, SK_ColorWHITE
         };
-        SkAutoTUnref<SkShader> shader(SkGradientShader::CreateLinear(
-                    pts, colors, nullptr, SK_ARRAY_COUNT(colors), SkShader::kClamp_TileMode
-        ));
-        paint.setShader(shader);
+        paint.setShader(SkGradientShader::MakeLinear(pts, colors, nullptr, SK_ARRAY_COUNT(colors),
+                                                     SkShader::kClamp_TileMode));
         canvas.drawPaint(paint);
     }
 };