Use IndexContributor(s) in LocalIndex.

pkg/analysis_server/lib/src/services/index/local_memory_index.dart

Index: pkg/analysis_server/lib/src/services/index/local_memory_index.dart
diff --git a/pkg/analysis_server/lib/src/services/index/local_memory_index.dart b/pkg/analysis_server/lib/src/services/index/local_memory_index.dart
index 7e2c8fc65a9b5838a2a344b78c4ab3fe2df39f72..0aab0c3eb171657ff3090bbf6fe4e871ee965fae 100644
--- a/pkg/analysis_server/lib/src/services/index/local_memory_index.dart
+++ b/pkg/analysis_server/lib/src/services/index/local_memory_index.dart
@@ -4,10 +4,15 @@
 
 library services.index.memory_file_index;
 
+import 'package:analysis_server/analysis/index_core.dart';
 import 'package:analysis_server/src/services/index/index.dart';
+import 'package:analysis_server/src/services/index/index_contributor.dart';
 import 'package:analysis_server/src/services/index/local_index.dart';
 import 'package:analysis_server/src/services/index/store/memory_node_manager.dart';
 
 Index createLocalMemoryIndex() {
-  return new LocalIndex(new MemoryNodeManager());
+  MemoryNodeManager nodeManager = new MemoryNodeManager();
+  LocalIndex index = new LocalIndex(nodeManager);
+  index.contributors = <IndexContributor>[new DartIndexContributor()];
+  return index;
 }