webui fixes for 0.8.9

test/observe_test.dart

Index: test/observe_test.dart
diff --git a/test/observe_test.dart b/test/observe_test.dart
index a4ccb40b33a4274d16e7f06701941a4887d043e1..194aca521688a29c8c1e6a413743d17d3f6e30a5 100644
--- a/test/observe_test.dart
+++ b/test/observe_test.dart
@@ -132,7 +132,7 @@ main() {
 
         // This will not affect the other observer, so it still gets the event.
         unobserve();
-        runAsync(() => t.value = 777);
+        scheduleMicrotask(() => t.value = 777);
       }));
       int count = 0;
       observe(() => t.value + 1000, expectAsync1((n) {