switch surface to sk_sp

bench/MergeBench.cpp

Index: bench/MergeBench.cpp
diff --git a/bench/MergeBench.cpp b/bench/MergeBench.cpp
index b24f988ded06a96f814bebc151284d976d642165..e1f7d97b5eb5483293f5850567a38b1816c07990 100644
--- a/bench/MergeBench.cpp
+++ b/bench/MergeBench.cpp
@@ -51,7 +51,7 @@ private:
     }
 
     void make_bitmap() {
-        SkAutoTUnref<SkSurface> surface(SkSurface::NewRasterN32Premul(80, 80));
+        auto surface(SkSurface::MakeRasterN32Premul(80, 80));
         surface->getCanvas()->clear(0x00000000);
         SkPaint paint;
         paint.setAntiAlias(true);
@@ -63,7 +63,7 @@ private:
     }
 
     void make_checkerboard() {
-        SkAutoTUnref<SkSurface> surface(SkSurface::NewRasterN32Premul(80, 80));
+        auto surface(SkSurface::MakeRasterN32Premul(80, 80));
         SkCanvas* canvas = surface->getCanvas();
         canvas->clear(0x00000000);
         SkPaint darkPaint;