Break up another large file

pkg/analyzer/test/src/task/dart_test.dart

 // Copyright (c) 2015, 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.test.src.task.dart_test;
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
+import 'package:analyzer/error/error.dart';
 import 'package:analyzer/src/context/cache.dart';
 import 'package:analyzer/src/dart/element/element.dart';
+import 'package:analyzer/src/error/codes.dart';
 import 'package:analyzer/src/generated/constant.dart';
 import 'package:analyzer/src/generated/engine.dart'
     show AnalysisOptions, AnalysisOptionsImpl, CacheState;
-import 'package:analyzer/src/generated/error.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/services/lint.dart';
 import 'package:analyzer/src/task/dart.dart';
 import 'package:analyzer/src/task/html.dart';
 import 'package:analyzer/src/task/strong/ast_properties.dart' as strong_ast;
 import 'package:analyzer/task/dart.dart';
 import 'package:analyzer/task/general.dart';
 import 'package:analyzer/task/model.dart';
@@ skipping 5514 matching lines @@
   /**
    * Fill [errorListener] with [result] errors in the current [task].
    */
   void _fillErrorListener(ResultDescriptor<List<AnalysisError>> result) {
     List<AnalysisError> errors = task.outputs[result] as List<AnalysisError>;
     expect(errors, isNotNull, reason: result.name);
     errorListener = new GatheringErrorListener();
     errorListener.addAll(errors);
   }
 }