Ignore typedef

dart/frog/leg/scanner/listener.dart

Index: dart/frog/leg/scanner/listener.dart
diff --git a/dart/frog/leg/scanner/listener.dart b/dart/frog/leg/scanner/listener.dart
index 37b143b821809a217bc59c43e6cdc3d98cf97213..9ac09ed81beeb9b63ec2afd23fc1e34479ac193f 100644
--- a/dart/frog/leg/scanner/listener.dart
+++ b/dart/frog/leg/scanner/listener.dart
@@ -540,7 +540,12 @@ class ElementListener extends Listener {
   }
 
   void endFunctionTypeAlias(Token typedefKeyword, Token endToken) {
-    listener.cancel("typedef is not implemented", token: typedefKeyword);
+    Identifier name = popNode();
+    TypeAnnotation returnType = popNode();
+  }
+
+  void handleVoidKeyword(Token token) {
+    pushNode(new TypeAnnotation(new Identifier(token), null));
   }
 
   void endTopLevelMethod(Token beginToken, Token getOrSet, Token endToken) {
@@ -921,10 +926,6 @@ class NodeListener extends ElementListener {
     pushNode(new Send(null, selector, arguments));
   }
 
-  void handleVoidKeyword(Token token) {
-    pushNode(new TypeAnnotation(new Identifier(token), null));
-  }
-
   void endFunctionBody(int count, Token beginToken, Token endToken) {
     pushNode(new Block(makeNodeList(count, beginToken, endToken, null)));
   }