anchor.diff:  
   @JS()
   @anonymous
  +@staticInterop
   abstract class CkFilterOptions {}
   
   @JS()
   @anonymous
  +@staticInterop
   class _CkCubicFilterOptions extends CkFilterOptions {
  -  external double get B;
  -  external double get C;
  -
     external factory _CkCubicFilterOptions({double B, double C});
   }
   
   @JS()
   @anonymous
  +@staticInterop
   class _CkTransformFilterOptions extends CkFilterOptions {
  -  external SkFilterMode get filter;
  -  external SkMipmapMode get mipmap;
  -
     external factory _CkTransformFilterOptions(
         {SkFilterMode filter, SkMipmapMode mipmap});
   }
  
positive.code: 
  @JS()
  @anonymous
  class SkColorFilter {
    external void delete();
  }
  
  @JS()
  class SkImageFilterNamespace {
    external SkImageFilter MakeBlur(
      double sigmaX,
      double sigmaY,
  
negative.code: 
  @JS()
  @anonymous
  @staticInterop
  class SkImageFilter {}
  
  extension SkImageFilterExtension on SkImageFilter {
    external void delete();
  }
  
  @JS()
  @staticInterop
  class SkPathNamespace {}
  
  extension SkPathNamespaceExtension on SkPathNamespace {
    /// Creates an [SkPath] using commands obtained from [SkPath.toCmds].
    external SkPath MakeFromCmds(List<dynamic> pathCommands);
  
  