Report UNMATCHED_TOKEN instead of EXTRANEOUS_MODIFIER

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

Index: pkg/compiler/lib/src/parser/element_listener.dart
diff --git a/pkg/compiler/lib/src/parser/element_listener.dart b/pkg/compiler/lib/src/parser/element_listener.dart
index 0cd21ac1351c180e8af0f8f6efdf53c1d4071e5d..6fe019cdae5ac31f2f075df7d495fc19a1d0c238 100644
--- a/pkg/compiler/lib/src/parser/element_listener.dart
+++ b/pkg/compiler/lib/src/parser/element_listener.dart
@@ -755,7 +755,8 @@ class ElementListener extends Listener {
     throw new ParserError(message);
   }
 
-  void reportError(Spannable spannable, MessageKind errorCode,
+  @override
+  void reportErrorHelper(Spannable spannable, MessageKind errorCode,
       [Map arguments = const {}]) {
     if (currentMemberHasParseError) return; // Error already reported.
     if (suppressParseErrors) return;