Implement SearchEngine.searchAllSubtypes() with the analysis driver.

pkg/analysis_server/test/services/search/hierarchy_test.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 test.services.src.search.hierarchy;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/services/index/index.dart';
 import 'package:analysis_server/src/services/search/hierarchy.dart';
@@ skipping 271 matching lines @@
     {
       ClassElement classB = findElement('B');
       List<Element> members = getMembers(classB);
       expect(
           members.map((e) => e.name),
           unorderedEquals(
               ['mb1', 'mb2', 'ma1', 'ma2', '==', 'toString', 'hashCode']));
     }
   }
 
-  Future test_getSubClasses() {
-    _indexTestUnit('''
-class A {}
-class B extends A {}
-class C extends B {}
-class D extends B implements A {}
-class M {}
-class E extends A with M {}
-''');
-    ClassElement classA = findElement("A");
-    ClassElement classB = findElement("B");
-    ClassElement classC = findElement("C");
-    ClassElement classD = findElement("D");
-    ClassElement classM = findElement("M");
-    ClassElement classE = findElement("E");
-    var futureA = getSubClasses(searchEngine, classA).then((subs) {
-      expect(subs, unorderedEquals([classB, classC, classD, classE]));
-    });
-    var futureB = getSubClasses(searchEngine, classB).then((subs) {
-      expect(subs, unorderedEquals([classC, classD]));
-    });
-    var futureC = getSubClasses(searchEngine, classC).then((subs) {
-      expect(subs, isEmpty);
-    });
-    var futureM = getSubClasses(searchEngine, classM).then((subs) {
-      expect(subs, unorderedEquals([classE]));
-    });
-    return Future.wait([futureA, futureB, futureC, futureM]);
-  }
-
   void test_getSuperClasses() {
     _indexTestUnit('''
 class A {}
 class B extends A {}
 class C extends B {}
 class D extends B implements A {}
 class M {}
 class E extends A with M {}
 class F implements A {}
 ''');
@@ skipping 39 matching lines @@
       Set<ClassElement> supers = getSuperClasses(classF);
       expect(supers, unorderedEquals([objectElement, classA]));
     }
   }
 
   void _indexTestUnit(String code) {
     resolveTestUnit(code);
     index.indexUnit(testUnit);
   }
 }