add Parser.withoutFasta constructor

pkg/analyzer/lib/src/generated/parser.dart

 // Copyright (c) 2014, 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 analyzer.parser;
 
 import 'dart:collection';
 import "dart:math" as math;
 
 import 'package:analyzer/dart/ast/ast.dart';
@@ skipping 266 matching lines @@
 
   /**
    * Initialize a newly created parser to parse tokens in the given [_source]
    * and to report any errors that are found to the given [_errorListener].
    */
   factory Parser(Source source, AnalysisErrorListener errorListener,
       {bool useFasta}) {
     if (useFasta ?? Parser.useFasta) {
       return new _Parser2(source, errorListener);
     } else {
-      return new Parser._(source, errorListener);
+      return new Parser.withoutFasta(source, errorListener);
     }
   }
 
-  Parser._(this._source, this._errorListener);
+  Parser.withoutFasta(this._source, this._errorListener);
 
   /**
    * Return the current token.
    */
   Token get currentToken => _currentToken;
 
   /**
    * Set the token with which the parse is to begin to the given [token].
    */
   void set currentToken(Token token) {
@@ skipping 8324 matching lines @@
     }
   }
 }
 
 /**
  * Instances of this class are thrown when the parser detects that AST has
  * too many nested expressions to be parsed safely and avoid possibility of
  * [StackOverflowError] in the parser or during later analysis.
  */
 class _TooDeepTreeError {}