Implement SearchEngine.searchAllSubtypes() with the analysis driver.

pkg/analysis_server/lib/src/domains/analysis/implemented_dart.dart

Index: pkg/analysis_server/lib/src/domains/analysis/implemented_dart.dart
diff --git a/pkg/analysis_server/lib/src/domains/analysis/implemented_dart.dart b/pkg/analysis_server/lib/src/domains/analysis/implemented_dart.dart
index 42e72137e535184fdf36a08b20fa70b62126204b..c284ee8a493e680851abc502b97a7d1bb7d32d68 100644
--- a/pkg/analysis_server/lib/src/domains/analysis/implemented_dart.dart
+++ b/pkg/analysis_server/lib/src/domains/analysis/implemented_dart.dart
@@ -5,7 +5,6 @@
 library domains.analysis.implemented_dart;
 
 import 'package:analysis_server/src/protocol_server.dart' as protocol;
-import 'package:analysis_server/src/services/search/hierarchy.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
 import 'package:analyzer/dart/element/element.dart';
 
@@ -31,7 +30,7 @@ class ImplementedComputer {
         continue;
       }
       // analyze ancestors
-      subtypes = await getSubClasses(searchEngine, type);
+      subtypes = await searchEngine.searchAllSubtypes(type);
       if (subtypes.isNotEmpty) {
         _addImplementedClass(type);
       }