Fix type issue in test (#38)

diff --git a/pubspec.yaml b/pubspec.yaml
index c841909..41ec037 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: observable
-version: 0.20.4
+version: 0.20.5-dev
 author: Dart Team <misc@dartlang.org>
 description: Support for marking objects as observable
 homepage: https://github.com/dart-lang/observable
diff --git a/test/collections/observable_list_test.dart b/test/collections/observable_list_test.dart
index 67e2587..8cb9618 100644
--- a/test/collections/observable_list_test.dart
+++ b/test/collections/observable_list_test.dart
@@ -129,7 +129,7 @@
 // These are the tests we will keep after deprecations occur.
 _runObservableListTests() {
   group('content changes', () {
-    Completer<List<ListChangeRecord>> completer;
+    Completer<List<ChangeRecord>> completer;
     List<String> previousState;
 
     ObservableList<String> list;
@@ -366,7 +366,7 @@
   });
 
   group('length changes', () {
-    Completer<List<ListChangeRecord>> completer;
+    Completer<List<ChangeRecord>> completer;
     ObservableList<String> list;
     Stream<List<ChangeRecord>> stream;
     StreamSubscription sub;