Convert SkAutoTUnref<SkData> to sk_sp<SkData>.

src/core/SkWriteBuffer.cpp

Index: src/core/SkWriteBuffer.cpp
diff --git a/src/core/SkWriteBuffer.cpp b/src/core/SkWriteBuffer.cpp
index e954399b0994eac3c352956b642b534eeefcdeda..33ac03b49de66e51d82fc1a0bb1a1a1c4c4c05b9 100644
--- a/src/core/SkWriteBuffer.cpp
+++ b/src/core/SkWriteBuffer.cpp
@@ -176,9 +176,9 @@ void SkBinaryWriteBuffer::writeImage(const SkImage* image) {
     this->writeInt(image->width());
     this->writeInt(image->height());
 
-    SkAutoTUnref<SkData> encoded(image->encode(this->getPixelSerializer()));
+    sk_sp<SkData> encoded(image->encode(this->getPixelSerializer()));
     if (encoded && encoded->size() > 0) {
-        write_encoded_bitmap(this, encoded, SkIPoint::Make(0, 0));
+        write_encoded_bitmap(this, encoded.get(), SkIPoint::Make(0, 0));
         return;
     }