Convert SkAutoTUnref<SkData> to sk_sp<SkData>.

src/ports/SkImageGeneratorCG.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkTypes.h"
 #if defined(SK_BUILD_FOR_MAC) || defined(SK_BUILD_FOR_IOS)
 
@@ skipping 17 matching lines @@
             int* ctableCount) override;
 
 private:
     /*
      * Takes ownership of the imageSrc
      * Refs the data
      */
     SkImageGeneratorCG(const SkImageInfo& info, const void* imageSrc, SkData* data);
 
     SkAutoTCallVProc<const void, CFRelease> fImageSrc;
-    SkAutoTUnref<SkData>                    fData;
+    sk_sp<SkData>                           fData;
 
     typedef SkImageGenerator INHERITED;
 };
 
 #endif //defined(SK_BUILD_FOR_MAC) || defined(SK_BUILD_FOR_IOS)