anchor.diff:    /// element.
     List<ParameterElement> _parameters;
   
  -  /// The declared return type of this executable element.
  -  DartType _declaredReturnType;
  -
     /// The inferred return type of this executable element.
     DartType _returnType;
   
  
positive.code: 
    @override
    DartType get returnType {
      if (linkedNode != null) {
        if (_returnType != null) return _returnType;
        var context = enclosingUnit.linkedContext;
        return _returnType = context.getReturnType(linkedNode);
      }
      return _returnType ?? _declaredReturnType;
    }
  
    void set returnType(DartType returnType) {
  
negative.code:       return linkedContext.getCodeOffset(linkedNode);
      }
      return super.codeOffset;
    }
  
    @override
  