anchor.diff:  
     /// Return extensions for the [type] that match the given [name] in the
     /// current scope.
  -  List<InstantiatedExtension> _getApplicable(
  +  List<_InstantiatedExtension> _getApplicable(
         DartType type, String name, ElementKind kind) {
       var candidates = _getExtensionsWithMember(name, kind);
   
  -    var instantiatedExtensions = <InstantiatedExtension>[];
  +    var instantiatedExtensions = <_InstantiatedExtension>[];
       for (var candidate in candidates) {
         var typeParameters = candidate.extension.typeParameters;
         var inferrer = GenericInferrer(
  
positive.code:     ).substituteType(extension.extendedType);
    }
  
    bool _isMoreSpecific(InstantiatedExtension e1, InstantiatedExtension e2) {
      var t10 = e1.element.extendedType;
      var t20 = e2.element.extendedType;
      var t11 = e1._extendedType;
  
negative.code:       }
  
        instantiatedExtensions.add(
          _InstantiatedExtension(
            candidate.extension,
            extendedType,
            // TODO(scheglov) Hm... Maybe not use from3(), but identify null subst?
  