Include comments when parsing with Fasta in file_state.

pkg/analyzer/lib/src/dart/analysis/file_state.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 file.
 
 import 'dart:convert';
 import 'dart:typed_data';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/error/listener.dart';
@@ skipping 339 matching lines @@
   }
 
   /**
    * Return a new parsed unresolved [CompilationUnit].
    */
   CompilationUnit parse(AnalysisErrorListener errorListener) {
     AnalysisOptions analysisOptions = _fsState._analysisOptions;
 
     if (USE_FASTA_PARSER) {
       try {
-        fasta.ScannerResult scanResult = fasta.scan(_contentBytes);
+        fasta.ScannerResult scanResult =
+            fasta.scan(_contentBytes, includeComments: true);
 
         var astBuilder = new fasta.AstBuilder(
             new ErrorReporter(errorListener, source),
             null,
             null,
             new _FastaElementStoreProxy(),
             new _FastaEmptyScope(),
             uri);
         var parser = new fasta.Parser(astBuilder);
         parser.parseUnit(scanResult.tokens);
@@ skipping 430 matching lines @@
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }
 
 class _FastaEmptyScope extends fasta.Scope {
   _FastaEmptyScope() : super({}, null);
 }
 
 class _FastaInterfaceTypeProxy implements fasta.KernelInterfaceType {
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }