Switch new SkImageFilter internal methods over to sk_sp

src/effects/SkPaintImageFilter.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 "SkPaintImageFilter.h"
 #include "SkCanvas.h"
 #include "SkReadBuffer.h"
@@ skipping 15 matching lines @@
     SkPaint paint;
     buffer.readPaint(&paint);
     return Create(paint, &common.cropRect());
 }
 
 void SkPaintImageFilter::flatten(SkWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writePaint(fPaint);
 }
 
-SkSpecialImage* SkPaintImageFilter::onFilterImage(SkSpecialImage* source,
-                                                  const Context& ctx,
-                                                  SkIPoint* offset) const {
+sk_sp<SkSpecialImage> SkPaintImageFilter::onFilterImage(SkSpecialImage* source,
+                                                        const Context& ctx,
+                                                        SkIPoint* offset) const {
     SkIRect bounds;
     const SkIRect srcBounds = SkIRect::MakeWH(source->width(), source->height());
     if (!this->applyCropRect(ctx, srcBounds, &bounds)) {
         return nullptr;
     }
 
     SkImageInfo info = SkImageInfo::MakeN32(bounds.width(), bounds.height(),
                                             kPremul_SkAlphaType);
 
     sk_sp<SkSpecialSurface> surf(source->makeSurface(info));
@@ skipping 11 matching lines @@
     SkRect rect = SkRect::MakeIWH(bounds.width(), bounds.height());
     SkMatrix inverse;
     if (matrix.invert(&inverse)) {
         inverse.mapRect(&rect);
     }
     canvas->setMatrix(matrix);
     canvas->drawRect(rect, fPaint);
 
     offset->fX = bounds.fLeft;
     offset->fY = bounds.fTop;
-    return surf->makeImageSnapshot().release();
+    return surf->makeImageSnapshot();
 }
 
 bool SkPaintImageFilter::canComputeFastBounds() const {
     // http:skbug.com/4627: "make computeFastBounds and onFilterBounds() CropRect-aware"
     // computeFastBounds() doesn't currently take the crop rect into account,
     // so we can't compute it. If a full crop rect is set, we should return true here.
     return false;
 }
 
 #ifndef SK_IGNORE_TO_STRING
 void SkPaintImageFilter::toString(SkString* str) const {
     str->appendf("SkPaintImageFilter: (");
     str->append(")");
 }
 #endif