Remove union type support from analyzer.

pkg/analyzer/lib/src/generated/engine.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.
 
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library engine;
 
 import "dart:math" as math;
@@ skipping 5716 matching lines @@
    * The instrumentation service that is to be used by this analysis engine.
    */
   InstrumentationService _instrumentationService =
       InstrumentationService.NULL_SERVICE;
 
   /**
    * The partition manager being used to manage the shared partitions.
    */
   final PartitionManager partitionManager = new PartitionManager();
 
-  /**
-   * A flag indicating whether union types should be used.
-   */
-  bool enableUnionTypes = false;
-
-  /**
-   * A flag indicating whether union types should have strict semantics. This
-   * option has no effect when `enabledUnionTypes` is `false`.
-   */
-  bool strictUnionTypes = false;
-
   AnalysisEngine._();
 
   /**
    * Return the instrumentation service that is to be used by this analysis
    * engine.
    */
   InstrumentationService get instrumentationService => _instrumentationService;
 
   /**
    * Set the instrumentation service that is to be used by this analysis engine
@@ skipping 5909 matching lines @@
   visitElement(Element element) {
     if (element.id == _id) {
       result = element;
       throw new _ElementByIdFinderException();
     }
     super.visitElement(element);
   }
 }
 
 class _ElementByIdFinderException {}