Issue 27130. Fix applying changes to .analysis_options on save.

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.
 
 library analyzer.src.generated.engine;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
@@ skipping 209 matching lines @@
    * Apply the given [delta] to change the level of analysis that will be
    * performed for the sources known to this context.
    */
   void applyAnalysisDelta(AnalysisDelta delta);
 
   /**
    * Apply the changes specified by the given [changeSet] to this context. Any
    * analysis results that have been invalidated by these changes will be
    * removed.
    */
-  ApplyChangesStatus applyChanges(ChangeSet changeSet);
+  void applyChanges(ChangeSet changeSet);
 
   /**
    * Return the documentation comment for the given [element] as it appears in
    * the original source (complete with the beginning and ending delimiters) for
    * block documentation comments, or lines starting with `"///"` and separated
    * with `"\n"` characters for end-of-line documentation comments, or `null` if
    * the element does not have a documentation comment associated with it. This
    * can be a long-running operation if the information needed to access the
    * comment is not cached.
    *
@@ skipping 1265 matching lines @@
   List<ChangeNotice> get changeNotices => _notices;
 
   /**
    * Return `true` if there is more to be performed after the task that was
    * performed.
    */
   bool get hasMoreWork => _notices != null;
 }
 
 /**
- * The result of applying a [ChangeSet] to a [AnalysisContext].
- */
-class ApplyChangesStatus {
-  /**
-   * Is `true` if the given [ChangeSet] caused any changes in the context.
-   */
-  final bool hasChanges;
-
-  ApplyChangesStatus(this.hasChanges);
-}
-
-/**
  * Statistics about cache consistency validation.
  */
 class CacheConsistencyValidationStatistics {
   /**
    * Number of sources which were changed, but the context was not notified
    * about it, so this fact was detected only during cache consistency
    * validation.
    */
   int numOfChanged = 0;
 
@@ skipping 1173 matching lines @@
    * The data that was created from the source.
    */
   final E data;
 
   /**
    * Initialize a newly created holder to associate the given [data] with the
    * given [modificationTime].
    */
   TimestampedData(this.modificationTime, this.data);
 }