send status notification when analysis starts and ends

pkg/analysis_server/test/analysis_server_test.dart

Index: pkg/analysis_server/test/analysis_server_test.dart
diff --git a/pkg/analysis_server/test/analysis_server_test.dart b/pkg/analysis_server/test/analysis_server_test.dart
index 3fb4e27dda720639b95f658283b357cdd61d0ef9..24a630632d258efff2767224858be79369fc34fd 100644
--- a/pkg/analysis_server/test/analysis_server_test.dart
+++ b/pkg/analysis_server/test/analysis_server_test.dart
@@ -51,6 +51,15 @@ main() {
       return pumpEventQueue().then((_) {
         List<Notification> notifications = helper.channel.notificationsReceived;
         expect(notifications, isNot(isEmpty));
+        // expect at least one notification indicating analysis is in progress
+        expect(notifications.any((Notification notification) {
+          if (notification.event == SERVER_STATUS) {
+            Map analysisStatus = notification.params['analysis'];
+            return analysisStatus['analyzing'];
+          }
+          return false;
+        }), isTrue);
+        // the last notification should indicate that analysis is complete
         Notification notification = notifications[notifications.length - 1];
         Map analysisStatus = notification.params['analysis'];
         expect(analysisStatus['analyzing'], isFalse);