tests: s/SkAutoTUnref/sk_sp/

BUG=skia:

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4394

Change-Id: I088b3c6e2adff07abed1e8a50091cc0ec4a4109c
Reviewed-on: https://skia-review.googlesource.com/4394
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>
diff --git a/tests/DataRefTest.cpp b/tests/DataRefTest.cpp
index 72bad6f..ab33d8c 100644
--- a/tests/DataRefTest.cpp
+++ b/tests/DataRefTest.cpp
@@ -339,8 +339,8 @@
     SkRWBuffer buffer;
     buffer.append(gABC, 26);
 
-    SkAutoTUnref<SkROBuffer> roBuffer(buffer.newRBufferSnapshot());
-    SkROBuffer::Iter iter(roBuffer);
+    sk_sp<SkROBuffer> roBuffer(buffer.newRBufferSnapshot());
+    SkROBuffer::Iter iter(roBuffer.get());
     REPORTER_ASSERT(r, iter.data());
     REPORTER_ASSERT(r, iter.size() == 26);