Switch new SkImageFilter internal methods over to sk_sp

include/effects/SkColorFilterImageFilter.h

 /*
  * Copyright 2012 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkColorFilterImageFilter_DEFINED
 #define SkColorFilterImageFilter_DEFINED
 
 #include "SkImageFilter.h"
 
 class SkColorFilter;
 
 class SK_API SkColorFilterImageFilter : public SkImageFilter {
 public:
     static SkImageFilter* Create(SkColorFilter* cf, SkImageFilter* input = NULL,
                                  const CropRect* cropRect = NULL);
 
     SK_TO_STRING_OVERRIDE()
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkColorFilterImageFilter)
 
 protected:
     void flatten(SkWriteBuffer&) const override;
-    SkSpecialImage* onFilterImage(SkSpecialImage* source, const Context&,
-                                  SkIPoint* offset) const override;
+    sk_sp<SkSpecialImage> onFilterImage(SkSpecialImage* source, const Context&,
+                                        SkIPoint* offset) const override;
     bool onIsColorFilterNode(SkColorFilter**) const override;
     bool canComputeFastBounds() const override;
 
 private:
     SkColorFilterImageFilter(SkColorFilter* cf,
                              SkImageFilter* input,
                              const CropRect* cropRect);
 
     sk_sp<SkColorFilter> fColorFilter;
 
     typedef SkImageFilter INHERITED;
 };
 
 #endif