new handleInvalidTopLevelDeclaration event in fasta parser

pkg/analyzer/tool/summary/mini_ast.dart

 // Copyright (c) 2017, 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.
 
 import 'package:front_end/src/fasta/problems.dart'
     show internalProblem, unsupported;
 import 'package:front_end/src/fasta/messages.dart' show Message;
 import 'package:front_end/src/fasta/parser.dart';
 import 'package:front_end/src/fasta/source/stack_listener.dart';
 import 'package:front_end/src/scanner/token.dart';
@@ skipping 385 matching lines @@
 
   void handleIdentifier(Token token, IdentifierContext context) {
     if (context == IdentifierContext.enumValueDeclaration) {
       var comment = new Comment(token.precedingComments);
       push(new EnumConstantDeclaration(comment, null, token.lexeme));
     } else {
       push(token.lexeme);
     }
   }
 
+  @override
+  void handleInvalidTopLevelDeclaration(Token beginToken, Token endToken) {
+    debugEvent("InvalidTopLevelDeclaration");
+    pop(); // metadata star
+  }
+
   void handleLiteralInt(Token token) {
     debugEvent("LiteralInt");
     push(new IntegerLiteral(int.parse(token.lexeme)));
   }
 
   void handleLiteralNull(Token token) {
     debugEvent("LiteralNull");
     push(new UnknownExpression());
   }
 
@@ skipping 54 matching lines @@
   final String name;
 
   final List<TypeName> typeArguments;
 
   TypeName(this.name, this.typeArguments);
 }
 
 /// "Mini AST" representation of an expression which summary code generation
 /// need not be concerned about.
 class UnknownExpression extends Expression {}