src/gpu: s/SkAutoTUnref/sk_sp/g

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4527

Change-Id: I23f0548f98e7c355da05e143e8baa330d4bc04cc
Reviewed-on: https://skia-review.googlesource.com/4527
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>
diff --git a/src/gpu/batches/GrAAFillRectBatch.cpp b/src/gpu/batches/GrAAFillRectBatch.cpp
index 4f93adf..fd2a4c4 100644
--- a/src/gpu/batches/GrAAFillRectBatch.cpp
+++ b/src/gpu/batches/GrAAFillRectBatch.cpp
@@ -235,10 +235,10 @@
 
         size_t vertexStride = gp->getVertexStride();
 
-        SkAutoTUnref<const GrBuffer> indexBuffer(get_index_buffer(target->resourceProvider()));
+        sk_sp<const GrBuffer> indexBuffer(get_index_buffer(target->resourceProvider()));
         InstancedHelper helper;
         void* vertices = helper.init(target, kTriangles_GrPrimitiveType, vertexStride,
-                                     indexBuffer, kVertsPerAAFillRect,
+                                     indexBuffer.get(), kVertsPerAAFillRect,
                                      kIndicesPerAAFillRect, fRectCnt);
         if (!vertices || !indexBuffer) {
             SkDebugf("Could not allocate vertices\n");