fix memory leak, remake Imageshader to use sk_sp

src/image/SkImage.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkBitmapCache.h"
 #include "SkCanvas.h"
@@ skipping 90 matching lines @@
     if (as_IB(this)->getROPixels(&bm)) {
         bm.lockPixels();
         bm.unlockPixels();
     }
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 sk_sp<SkShader> SkImage::makeShader(SkShader::TileMode tileX, SkShader::TileMode tileY,
                                     const SkMatrix* localMatrix) const {
-    return SkImageShader::Make(this, tileX, tileY, localMatrix);
+    return SkImageShader::Make(sk_ref_sp(const_cast<SkImage*>(this)), tileX, tileY, localMatrix);
 }
 
 #ifdef SK_SUPPORT_LEGACY_CREATESHADER_PTR
 SkShader* SkImage::newShader(SkShader::TileMode tileX, SkShader::TileMode tileY,
                              const SkMatrix* localMatrix) const {
     return this->makeShader(tileX, tileY, localMatrix).release();
 }
 #endif
 
 SkData* SkImage::encode(SkImageEncoder::Type type, int quality) const {
@@ skipping 382 matching lines @@
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 #include "SkImageDeserializer.h"
 
 sk_sp<SkImage> SkImageDeserializer::makeFromData(SkData* data, const SkIRect* subset) {
     return SkImage::MakeFromEncoded(sk_ref_sp(data), subset);
 }
 sk_sp<SkImage> SkImageDeserializer::makeFromMemory(const void* data, size_t length,
                                                    const SkIRect* subset) {
     return SkImage::MakeFromEncoded(SkData::MakeWithCopy(data, length), subset);
 }