Always set correspondingStaticParameters and correspondingPropagatedParameters, to clear when we don

pkg/analyzer/lib/src/dart/ast/ast.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.src.dart.ast.ast;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
@@ skipping 380 matching lines @@
     ..add(leftParenthesis)
     ..addAll(_arguments)
     ..add(rightParenthesis);
 
   List<ParameterElement> get correspondingPropagatedParameters =>
       _correspondingPropagatedParameters;
 
   @override
   void set correspondingPropagatedParameters(
       List<ParameterElement> parameters) {
-    if (parameters.length != _arguments.length) {
+    if (parameters != null && parameters.length != _arguments.length) {
       throw new IllegalArgumentException(
           "Expected ${_arguments.length} parameters, not ${parameters.length}");
     }
     _correspondingPropagatedParameters = parameters;
   }
 
   List<ParameterElement> get correspondingStaticParameters =>
       _correspondingStaticParameters;
 
   @override
   void set correspondingStaticParameters(List<ParameterElement> parameters) {
-    if (parameters.length != _arguments.length) {
+    if (parameters != null && parameters.length != _arguments.length) {
       throw new IllegalArgumentException(
           "Expected ${_arguments.length} parameters, not ${parameters.length}");
     }
     _correspondingStaticParameters = parameters;
   }
 
   @override
   Token get endToken => rightParenthesis;
 
   @override
@@ skipping 10619 matching lines @@
 
   @override
   dynamic/*=E*/ accept/*<E>*/(AstVisitor/*<E>*/ visitor) =>
       visitor.visitYieldStatement(this);
 
   @override
   void visitChildren(AstVisitor visitor) {
     _expression?.accept(visitor);
   }
 }