Potential fix for SpecialImageTest memory leak

src/core/SkSpecialImage.cpp

 /*
  * 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 "SkSpecialImage.h"
 
 #if SK_SUPPORT_GPU
 #include "GrTexture.h"
@@ skipping 87 matching lines @@
 
 bool SkSpecialImage::testingOnlyGetROPixels(SkBitmap* result) const {
     return as_SIB(this)->testingOnlyOnGetROPixels(result);
 }
 
 sk_sp<SkSpecialSurface> SkSpecialImage::makeSurface(const SkImageInfo& info) const {
     return as_SIB(this)->onMakeSurface(info);
 }
 
 sk_sp<SkSurface> SkSpecialImage::makeTightSurface(const SkImageInfo& info) const {
-    sk_sp<SkSurface> tmp(SkRef(as_SIB(this)->onMakeTightSurface(info)));
+    sk_sp<SkSurface> tmp(as_SIB(this)->onMakeTightSurface(info));
     return tmp;
 }
 
 sk_sp<SkSpecialImage> SkSpecialImage::makeSubset(const SkIRect& subset) const {
     return as_SIB(this)->onMakeSubset(subset);
 }
 
 sk_sp<SkImage> SkSpecialImage::makeTightSubset(const SkIRect& subset) const {
     return as_SIB(this)->onMakeTightSubset(subset);
 }
@@ skipping 416 matching lines @@
 
 sk_sp<SkSpecialImage> SkSpecialImage::MakeFromGpu(SkImageFilter::Proxy* proxy,
                                                   const SkIRect& subset,
                                                   uint32_t uniqueID,
                                                   GrTexture* tex,
                                                   SkAlphaType at) {
     return nullptr;
 }
 
 #endif