Replace computeNode() with AstProvider in search.

pkg/analysis_server/test/services/search/hierarchy_test.dart

Index: pkg/analysis_server/test/services/search/hierarchy_test.dart
diff --git a/pkg/analysis_server/test/services/search/hierarchy_test.dart b/pkg/analysis_server/test/services/search/hierarchy_test.dart
index e8638dcbe8f29c6424fba899b50a6cbebe19a11f..9f23cf795ce56951bc063433e2b6c3c35fd6f79c 100644
--- a/pkg/analysis_server/test/services/search/hierarchy_test.dart
+++ b/pkg/analysis_server/test/services/search/hierarchy_test.dart
@@ -12,6 +12,7 @@ import 'package:analysis_server/src/services/search/search_engine.dart';
 import 'package:analysis_server/src/services/search/search_engine_internal.dart';
 import 'package:analysis_server/src/services/search/search_engine_internal2.dart';
 import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/src/dart/analysis/ast_provider_context.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
@@ -368,7 +369,8 @@ class HierarchyTest extends AbstractHierarchyTest {
   void setUp() {
     super.setUp();
     index = createMemoryIndex();
-    searchEngine = new SearchEngineImpl(index);
+    searchEngine =
+        new SearchEngineImpl(index, (_) => new AstProviderForContext(context));
   }
 
   Future<Null> _indexTestUnit(String code) async {