Implement cc::FilterOperation StructTraits

cc/output/filter_operation.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_OUTPUT_FILTER_OPERATION_H_
 #define CC_OUTPUT_FILTER_OPERATION_H_
 
 #include <memory>
 
 #include "base/logging.h"
@@ skipping 31 matching lines @@
     BLUR,
     DROP_SHADOW,
     COLOR_MATRIX,
     ZOOM,
     REFERENCE,
     SATURATING_BRIGHTNESS,  // Not used in CSS/SVG.
     ALPHA_THRESHOLD,  // Not used in CSS/SVG.
     FILTER_TYPE_LAST = ALPHA_THRESHOLD
   };
 
+  FilterOperation();
+
   FilterOperation(const FilterOperation& other);
 
   ~FilterOperation();
 
   FilterType type() const { return type_; }
 
   float amount() const {
     DCHECK_NE(type_, COLOR_MATRIX);
     DCHECK_NE(type_, REFERENCE);
     return amount_;
@@ skipping 197 matching lines @@
   SkColor drop_shadow_color_;
   sk_sp<SkImageFilter> image_filter_;
   SkScalar matrix_[20];
   int zoom_inset_;
   SkRegion region_;
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_FILTER_OPERATION_H_