change flattenable factory to return sk_sp

src/effects/gradients/SkSweepGradient.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 "SkSweepGradient.h"
 
 static SkMatrix translate(SkScalar dx, SkScalar dy) {
@@ skipping 11 matching lines @@
 }
 
 SkShader::GradientType SkSweepGradient::asAGradient(GradientInfo* info) const {
     if (info) {
         commonAsAGradient(info);
         info->fPoint[0] = fCenter;
     }
     return kSweep_GradientType;
 }
 
-SkFlattenable* SkSweepGradient::CreateProc(SkReadBuffer& buffer) {
+sk_sp<SkFlattenable> SkSweepGradient::CreateProc(SkReadBuffer& buffer) {
     DescriptorScope desc;
     if (!desc.unflatten(buffer)) {
         return nullptr;
     }
     const SkPoint center = buffer.readPoint();
     return SkGradientShader::MakeSweep(center.x(), center.y(), desc.fColors, desc.fPos,
-                                       desc.fCount, desc.fGradFlags, desc.fLocalMatrix).release();
+                                       desc.fCount, desc.fGradFlags, desc.fLocalMatrix);
 }
 
 void SkSweepGradient::flatten(SkWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writePoint(fCenter);
 }
 
 size_t SkSweepGradient::onContextSize(const ContextRec&) const {
     return sizeof(SweepGradientContext);
 }
@@ skipping 210 matching lines @@
     str->appendScalar(fCenter.fX);
     str->append(", ");
     str->appendScalar(fCenter.fY);
     str->append(") ");
 
     this->INHERITED::toString(str);
 
     str->append(")");
 }
 #endif