Parse using FileState, so use all analysis options.

pkg/analyzer/lib/src/dart/analysis/analysis_impl.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:analyzer/context/declared_variables.dart';
 import 'package:analyzer/dart/ast/ast.dart';
-import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/error/listener.dart';
 import 'package:analyzer/src/context/context.dart';
 import 'package:analyzer/src/dart/analysis/file_state.dart';
 import 'package:analyzer/src/dart/ast/ast.dart';
 import 'package:analyzer/src/dart/constant/evaluation.dart';
 import 'package:analyzer/src/dart/constant/utilities.dart';
-import 'package:analyzer/src/dart/scanner/scanner.dart';
 import 'package:analyzer/src/error/codes.dart';
 import 'package:analyzer/src/error/pending_error.dart';
 import 'package:analyzer/src/generated/declaration_resolver.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/error_verifier.dart';
-import 'package:analyzer/src/generated/parser.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/summary/package_bundle_reader.dart';
 import 'package:analyzer/src/task/dart.dart';
 import 'package:analyzer/src/task/strong/checker.dart';
 import 'package:front_end/src/dependency_walker.dart';
-import 'package:front_end/src/scanner/reader.dart';
 
 /**
  * Analyzer of Dart files.
  *
  * Work in progress, not ready to be used.
  */
 class AnalyzerImpl {
   final AnalysisOptions _analysisOptions;
   final DeclaredVariables _declaredVariables;
   final SourceFactory _sourceFactory;
@@ skipping 288 matching lines @@
       }
     }
     return null;
   }
 
   /**
    * Return a new parsed unresolved [CompilationUnit].
    */
   CompilationUnit _parse(FileState file) {
     RecordingErrorListener errorListener = _getErrorListener(file);
+    String content = file.content;
+    CompilationUnit unit = file.parse(errorListener);
 
-    String content = file.content;
-
-    CharSequenceReader reader = new CharSequenceReader(content);
-    Scanner scanner = new Scanner(file.source, reader, errorListener);
-    scanner.scanGenericMethodComments = _analysisOptions.strongMode;
-    Token token = scanner.tokenize();
-    LineInfo lineInfo = new LineInfo(scanner.lineStarts);
-
+    LineInfo lineInfo = unit.lineInfo;
     _fileToLineInfo[file] = lineInfo;
     _fileToIgnoreInfo[file] = IgnoreInfo.calculateIgnores(content, lineInfo);
 
-    Parser parser = new Parser(file.source, errorListener);
-    parser.parseGenericMethodComments = _analysisOptions.strongMode;
-    parser.enableUriInPartOf = _analysisOptions.enableUriInPartOf;
-    CompilationUnit unit = parser.parseCompilationUnit(token);
-    unit.lineInfo = lineInfo;
     return unit;
   }
 
   void _resolveDirectives(Map<FileState, CompilationUnit> units) {
     CompilationUnit definingCompilationUnit = units[_library];
 
     var uriToElement = <Uri, CompilationUnitElement>{};
     for (CompilationUnitElement partElement in _libraryElement.units) {
       uriToElement[partElement.source.uri] = partElement;
     }
@@ skipping 358 matching lines @@
 }
 
 /**
  * Either the name or the source associated with a part-of directive.
  */
 class _NameOrSource {
   final String name;
   final Source source;
   _NameOrSource(this.name, this.source);
 }