Update parser so tests pass.

pkg/dart_parser/lib/parser.dart

-// Copyright (c) 2016, 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.md file.
-
-library parser;
-
-import 'package:scanner/src/token.dart' show
-    Token;
-
-import 'src/listener.dart' show
-    Listener;
-
-import 'src/parser.dart' show
-    Parser;
-
-import 'src/listener.dart' show
-    ParserError;
-
-export 'src/listener.dart' show
-    ParserError;
-
-List<ParserError> parse(Token tokens, {bool enableGenericMethodSyntax: false}) {
-  Listener listener = new Listener();
-  Parser parser = new Parser(listener,
-      enableGenericMethodSyntax: enableGenericMethodSyntax);
-  parser.parseUnit(tokens);
-  return listener.recoverableErrors;
-}