Make some pkg tests less timing-dependent.

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 c238d5954f51e82351e6a5f7717f9f07e33ac117..2fcb0498b673d2dc6c1e6cbd9602fc1d901102c0 100644
--- a/pkg/analysis_server/test/analysis_server_test.dart
+++ b/pkg/analysis_server/test/analysis_server_test.dart
@@ -338,12 +338,12 @@ import "../foo/foo.dart";
       subscriptions[service] = <String>[bar.path].toSet();
     }
     server.setAnalysisSubscriptions(subscriptions);
-    await pumpEventQueue(1000);
+    await server.onAnalysisComplete;
     expect(server.statusAnalyzing, isFalse);
     channel.notificationsReceived.clear();
     server.updateContent(
         '0', {bar.path: new AddContentOverlay('library bar; void f() {}')});
-    await pumpEventQueue(1000);
+    await server.onAnalysisComplete;
     expect(server.statusAnalyzing, isFalse);
     expect(channel.notificationsReceived, isNotEmpty);
     Set<String> notificationTypesReceived = new Set<String>();