Revert 6ad38498c8673f1fbe3e12c49b1cf590305676dd (PARSED_UNIT).

pkg/analyzer/lib/src/plugin/engine_plugin.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.src.plugin.engine_plugin;
 
 import 'package:analyzer/plugin/task.dart';
 import 'package:analyzer/src/generated/engine.dart'
     show InternalAnalysisContext;
 import 'package:analyzer/src/generated/error.dart' show AnalysisError;
@@ skipping 152 matching lines @@
   void registerExtensions(RegisterExtension registerExtension) {
     _registerTaskExtensions(registerExtension);
     _registerWorkManagerFactoryExtensions(registerExtension);
     _registerDartErrorsForSource(registerExtension);
     _registerDartErrorsForUnit(registerExtension);
     _registerHtmlErrors(registerExtension);
   }
 
   void _registerDartErrorsForSource(RegisterExtension registerExtension) {
     registerExtension(DART_ERRORS_FOR_SOURCE_EXTENSION_POINT_ID, PARSE_ERRORS);
-    registerExtension(DART_ERRORS_FOR_SOURCE_EXTENSION_POINT_ID, RESOLVE_DIRECTIVES_ERRORS);
     registerExtension(DART_ERRORS_FOR_SOURCE_EXTENSION_POINT_ID, SCAN_ERRORS);
   }
 
   void _registerDartErrorsForUnit(RegisterExtension registerExtension) {
     registerExtension(
         DART_ERRORS_FOR_UNIT_EXTENSION_POINT_ID, LIBRARY_UNIT_ERRORS);
   }
 
   void _registerHtmlErrors(RegisterExtension registerExtension) {
     registerExtension(HTML_ERRORS_EXTENSION_POINT_ID, HTML_DOCUMENT_ERRORS);
@@ skipping 41 matching lines @@
     registerExtension(
         taskId, PropagateVariableTypesInLibraryClosureTask.DESCRIPTOR);
     registerExtension(taskId, PropagateVariableTypesInLibraryTask.DESCRIPTOR);
     registerExtension(taskId, PropagateVariableTypesInUnitTask.DESCRIPTOR);
     registerExtension(taskId, PropagateVariableTypeTask.DESCRIPTOR);
     registerExtension(taskId, ReadyLibraryElement2Task.DESCRIPTOR);
     registerExtension(taskId, ReadyLibraryElement5Task.DESCRIPTOR);
     registerExtension(taskId, ReadyLibraryElement6Task.DESCRIPTOR);
     registerExtension(taskId, ReadyResolvedUnitTask.DESCRIPTOR);
     registerExtension(taskId, ResolveConstantExpressionTask.DESCRIPTOR);
-    registerExtension(taskId, ResolveDirectivesTask.DESCRIPTOR);
     registerExtension(taskId, ResolveDirectiveElementsTask.DESCRIPTOR);
     registerExtension(taskId, ResolveInstanceFieldsInUnitTask.DESCRIPTOR);
     registerExtension(taskId, ResolveLibraryReferencesTask.DESCRIPTOR);
     registerExtension(taskId, ResolveLibraryTask.DESCRIPTOR);
     registerExtension(taskId, ResolveLibraryTypeNamesTask.DESCRIPTOR);
     registerExtension(taskId, ResolveTopLevelLibraryTypeBoundsTask.DESCRIPTOR);
     registerExtension(taskId, ResolveTopLevelUnitTypeBoundsTask.DESCRIPTOR);
     registerExtension(taskId, ResolveUnitTask.DESCRIPTOR);
     registerExtension(taskId, ResolveUnitTypeNamesTask.DESCRIPTOR);
     registerExtension(taskId, ResolveVariableReferencesTask.DESCRIPTOR);
@@ skipping 30 matching lines @@
  * passed to the extension manager to populate it.
  *
  * This annotation is not used at runtime; it is used to aid in static analysis
  * of the task model during development.
  */
 class ExtensionPointId {
   final String extensionPointId;
 
   const ExtensionPointId(this.extensionPointId);
 }