Record HAS_ANCESTOR relations into index.

pkg/analysis_server/lib/src/services/search/hierarchy.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 services.hierarchy;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analysis_server/src/services/search/element_visitors.dart';
@@ skipping 114 matching lines @@
     members.addAll(getClassMembers(superClass));
   }
   return members;
 }
 
 /**
  * Returns a [Set] with all direct and indirect subclasses of [seed].
  */
 Future<Set<ClassElement>> getSubClasses(
     SearchEngine searchEngine, ClassElement seed) {
-  Set<ClassElement> subs = new HashSet<ClassElement>();
-  // prepare queue
-  List<ClassElement> queue = new List<ClassElement>();
-  queue.add(seed);
-  // schedule subclasss search
-  addSubClasses() {
-    // add direct subclasses of the next class
-    while (queue.isNotEmpty) {
-      ClassElement clazz = queue.removeLast();
-      if (subs.add(clazz)) {
-        return getDirectSubClasses(searchEngine, clazz).then((directSubs) {
-          queue.addAll(directSubs);
-          return new Future(addSubClasses);
-        });
-      }
+  return searchEngine.searchAllSubtypes(seed).then((List<SearchMatch> matches) {
+    Set<ClassElement> ancestors = new HashSet<ClassElement>();
+    for (SearchMatch match in matches) {
+      ClassElement ancestor = match.element;
+      ancestors.add(ancestor);
     }
-    // done
-    subs.remove(seed);
-    return subs;
-  }
-  return new Future(addSubClasses);
+    return ancestors;
+  });
 }
 
 /**
  * Returns a [Set] with all direct and indirect superclasses of [seed].
  */
 Set<ClassElement> getSuperClasses(ClassElement seed) {
   Set<ClassElement> result = new HashSet<ClassElement>();
   // prepare queue
   List<ClassElement> queue = new List<ClassElement>();
   queue.add(seed);
@@ skipping 26 matching lines @@
  * its variable, otherwise returns [element].
  */
 Element getSyntheticAccessorVariable(Element element) {
   if (element is PropertyAccessorElement) {
     if (element.isSynthetic) {
       return element.variable;
     }
   }
   return element;
 }