new handleInvalidTopLevelDeclaration event in fasta parser

pkg/front_end/lib/src/fasta/source/diet_listener.dart

Index: pkg/front_end/lib/src/fasta/source/diet_listener.dart
diff --git a/pkg/front_end/lib/src/fasta/source/diet_listener.dart b/pkg/front_end/lib/src/fasta/source/diet_listener.dart
index 31d4daa38e094325d76082a9726969dc28880dcb..5c2a211b8ee883f3adbbc13b129a810ea180ebfd 100644
--- a/pkg/front_end/lib/src/fasta/source/diet_listener.dart
+++ b/pkg/front_end/lib/src/fasta/source/diet_listener.dart
@@ -89,6 +89,12 @@ class DietListener extends StackListener {
   }
 
   @override
+  void handleInvalidTopLevelDeclaration(Token beginToken, Token endToken) {
+    debugEvent("InvalidTopLevelDeclaration");
+    pop(); // metadata star
+  }
+
+  @override
   void endMetadata(Token beginToken, Token periodBeforeName, Token endToken) {
     debugEvent("Metadata");
     discard(periodBeforeName == null ? 1 : 2);