Convert SkAutoTUnref<SkData> to sk_sp<SkData>.

gm/image.cpp

Index: gm/image.cpp
diff --git a/gm/image.cpp b/gm/image.cpp
index b57ec3a687e4b93c75ef3c27b2b97220945374e1..a67ed202dbea196f157d3d55e6877cc6f1de2c9c 100644
--- a/gm/image.cpp
+++ b/gm/image.cpp
@@ -349,14 +349,14 @@ static SkImageGenerator* gen_picture(const SkImageInfo& info) {
 
 static SkImageGenerator* gen_png(const SkImageInfo& info) {
     sk_sp<SkImage> image(make_raster(info, nullptr, draw_opaque_contents));
-    SkAutoTUnref<SkData> data(image->encode(SkImageEncoder::kPNG_Type, 100));
-    return SkImageGenerator::NewFromEncoded(data);
+    sk_sp<SkData> data(image->encode(SkImageEncoder::kPNG_Type, 100));
+    return SkImageGenerator::NewFromEncoded(data.get());
 }
 
 static SkImageGenerator* gen_jpg(const SkImageInfo& info) {
     sk_sp<SkImage> image(make_raster(info, nullptr, draw_opaque_contents));
-    SkAutoTUnref<SkData> data(image->encode(SkImageEncoder::kJPEG_Type, 100));
-    return SkImageGenerator::NewFromEncoded(data);
+    sk_sp<SkData> data(image->encode(SkImageEncoder::kJPEG_Type, 100));
+    return SkImageGenerator::NewFromEncoded(data.get());
 }
 
 typedef SkImageGenerator* (*GeneratorMakerProc)(const SkImageInfo&);