Parse optional and named parameters.

pkg/compiler/lib/src/parser/node_listener.dart

Index: pkg/compiler/lib/src/parser/node_listener.dart
diff --git a/pkg/compiler/lib/src/parser/node_listener.dart b/pkg/compiler/lib/src/parser/node_listener.dart
index b5cbad61da0b334b0f4874726239afca58218d09..b1295c55c0a7b033b081c43934a2129c8bbcafeb 100644
--- a/pkg/compiler/lib/src/parser/node_listener.dart
+++ b/pkg/compiler/lib/src/parser/node_listener.dart
@@ -6,6 +6,8 @@ library dart2js.parser.node_listener;
 
 import '../common.dart';
 import '../elements/elements.dart' show CompilationUnitElement;
+import 'package:front_end/src/fasta/parser/parser.dart'
+    show FormalParameterType;
 import 'package:front_end/src/fasta/scanner/precedence.dart' as Precedence
     show INDEX_INFO;
 import 'package:front_end/src/fasta/scanner.dart' show StringToken, Token;
@@ -182,7 +184,7 @@ class NodeListener extends ElementListener {
   }
 
   @override
-  void endFormalParameter(Token thisKeyword) {
+  void endFormalParameter(Token thisKeyword, FormalParameterType kind) {
     Expression name = popNode();
     if (thisKeyword != null) {
       Identifier thisIdentifier = new Identifier(thisKeyword);
@@ -723,6 +725,10 @@ class NodeListener extends ElementListener {
   }
 
   @override
+  void handleFormalParameterWithoutValue(Token token) {

[Paul Berry, 2017/02/22 20:50:04]

Nit: run dartfmt

+  }
+
+  @override
   void endTryStatement(int catchCount, Token tryKeyword, Token finallyKeyword) {
     Block finallyBlock = null;
     if (finallyKeyword != null) {