improve fasta export directive recovery

pkg/analyzer/test/generated/parser_fasta_listener.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/fasta_codes.dart';
 import 'package:front_end/src/fasta/parser/identifier_context.dart'
     show IdentifierContext;
 import 'package:front_end/src/fasta/parser.dart' as fasta;
+import 'package:front_end/src/fasta/parser/token_stream_rewriter.dart';
 import 'package:front_end/src/fasta/scanner/token.dart' as fasta;
 import 'package:front_end/src/fasta/util/link.dart';
 import 'package:front_end/src/scanner/token.dart';
 import 'package:test/test.dart';
 
 /**
  * Proxy implementation of the fasta parser listener that
  * asserts begin/end pairs of events and forwards all events
  * to the specified listener.
  *
@@ skipping 33 matching lines @@
   }
 
   void end(String event) {
     expectIn(event);
     _stack.removeLast();
   }
 
   ForwardingTestListener(this.listener);
 
   @override
+  Token get firstToken => listener.firstToken;
+
+  @override
+  set firstToken(Token token) {
+    listener.firstToken = token;
+  }
+
+  @override
+  TokenStreamRewriter get rewriter => listener.rewriter;
+
+  @override
+  Uri get uri => listener.uri;
+
+  @override
   void beginArguments(Token token) {
     listener.beginArguments(token);
     begin('Arguments');
   }
 
   @override
   void beginAssert(Token assertKeyword, fasta.Assert kind) {
     listener.beginAssert(assertKeyword, kind);
     begin('Assert');
   }
@@ skipping 1463 matching lines @@
     return listener.replaceTokenWithGenericCommentTypeAssign(
         tokenToStartReplacing, tokenWithComment);
     // TODO(danrubel): implement replaceTokenWithGenericCommentTypeAssign
   }
 
   @override
   set suppressParseErrors(bool value) {
     listener.suppressParseErrors = value;
     // TODO(danrubel): implement suppressParseErrors
   }
-
-  // TODO(danrubel): implement uri
-  @override
-  Uri get uri => listener.uri;
 }