change flattenable factory to return sk_sp

src/effects/SkColorFilterImageFilter.cpp

Index: src/effects/SkColorFilterImageFilter.cpp
diff --git a/src/effects/SkColorFilterImageFilter.cpp b/src/effects/SkColorFilterImageFilter.cpp
index a5904ea60b672d4c7041c88c9baa0fff2c3c183b..c1637d81284b062602954483a68a46cfc89aacdf 100644
--- a/src/effects/SkColorFilterImageFilter.cpp
+++ b/src/effects/SkColorFilterImageFilter.cpp
@@ -41,10 +41,10 @@ SkColorFilterImageFilter::SkColorFilterImageFilter(SkColorFilter* cf,
     , fColorFilter(SkRef(cf)) {
 }
 
-SkFlattenable* SkColorFilterImageFilter::CreateProc(SkReadBuffer& buffer) {
+sk_sp<SkFlattenable> SkColorFilterImageFilter::CreateProc(SkReadBuffer& buffer) {
     SK_IMAGEFILTER_UNFLATTEN_COMMON(common, 1);
     sk_sp<SkColorFilter> cf(buffer.readColorFilter());
-    return Create(cf.get(), common.getInput(0).get(), &common.cropRect());
+    return sk_sp<SkFlattenable>(Create(cf.get(), common.getInput(0).get(), &common.cropRect()));
 }
 
 void SkColorFilterImageFilter::flatten(SkWriteBuffer& buffer) const {