Add closeBraceTokenFor and use it instead of BeginToken.

pkg/front_end/lib/src/fasta/parser/listener.dart

 // Copyright (c) 2012, 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.
 
 library fasta.parser.listener;
 
-import '../../scanner/token.dart' show BeginToken, Token, TokenType;
+import '../../scanner/token.dart' show Token, TokenType;
 
 import '../fasta_codes.dart' show Message;
 
 import '../util/link.dart' show Link;
 
 import 'assert.dart' show Assert;
 
 import 'formal_parameter_kind.dart' show FormalParameterKind;
 
 import 'identifier_context.dart' show IdentifierContext;
@@ skipping 961 matching lines @@
 
   void handleSymbolVoid(Token token) {
     logEvent("SymbolVoid");
   }
 
   /// Handle the end of a construct of the form "operator <token>".
   void handleOperatorName(Token operatorKeyword, Token token) {
     logEvent("OperatorName");
   }
 
-  void handleParenthesizedExpression(BeginToken token) {
+  void handleParenthesizedExpression(Token token) {
     logEvent("ParenthesizedExpression");
   }
 
   /// Handle a construct of the form "identifier.identifier" occurring in a part
   /// of the grammar where expressions in general are not allowed.
   /// Substructures:
   /// - Qualified identifier (before the period)
   /// - Identifier (after the period)
   void handleQualified(Token period) {
     logEvent("Qualified");
@@ skipping 101 matching lines @@
   void discardTypeReplacedWithCommentTypeAssign() {}
 
   /// Creates a new synthetic token whose `next` pointer points to [next].
   ///
   /// If [next] is `null`, `null` is returned.
   Token newSyntheticToken(Token next) {
     if (next == null) return null;
     return new Token(TokenType.RECOVERY, next.charOffset)..next = next;
   }
 }