Replace many skia::RefPtr with sk_sp<> in cc/

cc/output/filter_operation.cc

Index: cc/output/filter_operation.cc
diff --git a/cc/output/filter_operation.cc b/cc/output/filter_operation.cc
index 72c03718efc5540a5dace726a78443728b9b6222..1d253c8677f8d716bd227163f3ee8aa6272305c0 100644
--- a/cc/output/filter_operation.cc
+++ b/cc/output/filter_operation.cc
@@ -86,9 +86,8 @@ FilterOperation::FilterOperation(FilterType type, float amount, int inset)
   memset(matrix_, 0, sizeof(matrix_));
 }
 
-FilterOperation::FilterOperation(
-    FilterType type,
-    const skia::RefPtr<SkImageFilter>& image_filter)
+FilterOperation::FilterOperation(FilterType type,
+                                 sk_sp<SkImageFilter> image_filter)
     : type_(type),
       amount_(0),
       outer_threshold_(0),
@@ -164,8 +163,7 @@ static FilterOperation CreateNoOpFilter(FilterOperation::FilterType type) {
     case FilterOperation::SATURATING_BRIGHTNESS:
       return FilterOperation::CreateSaturatingBrightnessFilter(0.f);
     case FilterOperation::REFERENCE:
-      return FilterOperation::CreateReferenceFilter(
-          skia::RefPtr<SkImageFilter>());
+      return FilterOperation::CreateReferenceFilter(nullptr);
     case FilterOperation::ALPHA_THRESHOLD:
       return FilterOperation::CreateAlphaThresholdFilter(SkRegion(), 1.f, 0.f);
   }