anchor.diff:  import 'package:analyzer/src/dart/resolver/method_invocation_resolver.dart';
   import 'package:analyzer/src/dart/resolver/resolution_result.dart';
   import 'package:analyzer/src/error/codes.dart';
  +import 'package:analyzer/src/generated/element_type_provider.dart';
   import 'package:analyzer/src/generated/engine.dart';
   import 'package:analyzer/src/generated/resolver.dart';
   import 'package:analyzer/src/generated/super_context.dart';
  
positive.code:     if (executableElement == null) {
        return null;
      }
      List<ParameterElement> parameters = executableElement.parameters;
      return _resolveArgumentsToParameters(argumentList, parameters);
    }
  
  
negative.code:     if (expression is NullLiteral) {
        return _resolver.typeProvider.nullType;
      }
      DartType type = read
          ? getReadType(expression, elementTypeProvider: _elementTypeProvider)
          : expression.staticType;
      return _resolveTypeParameter(type);
    }
  
  