Remove more dead code from analysis server

pkg/analysis_server/lib/plugin/analysis/analysis_domain.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.
 
 /**
  * Support for client code that interacts with the analysis domain of an
  * analysis server.
  *
  * Plugins can gain access to the request handler that implements the analysis
  * domain in order to extend the functionality of that domain. The class
  * [AnalysisDomain] defines the API of the analysis domain that plugins can use.
  *
  * If a plugin is interested in gaining access to the analysis domain, it should
  * register a function by including code like the following in the plugin's
  * registerExtensions method:
  *
  *     AnalysisDomain analysisDomain;
  *
  *     @override
  *     void registerExtensions(RegisterExtension registerExtension) {
  *       ...
  *       registerExtension(
  *           SET_ANALYSIS_DOMAIN_EXTENSION_POINT_ID,
  *           (AnalysisDomain domain) => analysisDomain = domain);
  *       ...
  *     }
  */
-import 'dart:async';
-
 import 'package:analysis_server/protocol/protocol_generated.dart'
     show AnalysisService;
 import 'package:analysis_server/src/plugin/server_plugin.dart';
-import 'package:analyzer/src/generated/engine.dart'
-    show AnalysisContext, ResultChangedEvent;
+import 'package:analyzer/src/generated/engine.dart' show AnalysisContext;
 import 'package:analyzer/src/generated/source.dart' show Source;
-import 'package:analyzer/task/model.dart' show ResultDescriptor;
 import 'package:plugin/plugin.dart';
 
 /**
  * The identifier of the extension point that allows plugins to get access to an
  * [AnalysisDomain]. The object used as an extension must be a
  * [SetAnalysisDomain].
  */
 final String SET_ANALYSIS_DOMAIN_EXTENSION_POINT_ID = Plugin.join(
     ServerPlugin.UNIQUE_IDENTIFIER,
     ServerPlugin.SET_ANALISYS_DOMAIN_EXTENSION_POINT);
 
 /**
  * A function that is invoked after the analysis domain has been created and is
  * initialized.
  */
 typedef void SetAnalysisDomain(AnalysisDomain domain);
 
 /**
  * An object that gives plugins access to the analysis domain of the analysis
  * server.
  *
  * Clients may not extend, implement or mix-in this class.
  */
 abstract class AnalysisDomain {
   /**
-   * Return the stream that is notified when a new value for the given
-   * [result] is computed or invalidated.
-   *
-   * This method should be used by plugins that need to perform some additional
-   * processing after analysis has completed. One example would be a plugin that
-   * needed to send a notification to the client because some data was now
-   * invalidated.
-   */
-  Stream<ResultChangedEvent> onResultChanged(ResultDescriptor result);
-
-  /**
    * Schedule sending the given [service] notifications for the given [source]
    * in the given [context].
    */
   void scheduleNotification(
       AnalysisContext context, Source source, AnalysisService service);
 }