Stop using deprecated pkg/test apis

pkgs/watcher/pubspec.yaml

diff --git a/pkgs/watcher/pubspec.yaml b/pkgs/watcher/pubspec.yaml
index 6bdb39a..d1260d5 100644
--- a/pkgs/watcher/pubspec.yaml
+++ b/pkgs/watcher/pubspec.yaml
@@ -13,4 +13,4 @@
 dev_dependencies:
   benchmark_harness: '^1.0.4'
   scheduled_test: '^0.12.0'
-  test: '^0.12.0'
+  test: '^0.12.18+1'

pkgs/watcher/test/no_subscription/shared.dart

diff --git a/pkgs/watcher/test/no_subscription/shared.dart b/pkgs/watcher/test/no_subscription/shared.dart
index 52649f1..5858656 100644
--- a/pkgs/watcher/test/no_subscription/shared.dart
+++ b/pkgs/watcher/test/no_subscription/shared.dart
@@ -18,7 +18,7 @@
 
     // Subscribe to the events.
     var completer = new Completer();
-    var subscription = watcher.events.listen(expectAsync((event) {
+    var subscription = watcher.events.listen(expectAsync1((event) {
       expect(event, isWatchEvent(ChangeType.ADD, "file.txt"));
       completer.complete();
     }));
@@ -39,7 +39,7 @@
     // Then start listening again.
     schedule(() {
       completer = new Completer();
-      subscription = watcher.events.listen(expectAsync((event) {
+      subscription = watcher.events.listen(expectAsync1((event) {
         // We should get an event for the third file, not the one added while
         // we weren't subscribed.
         expect(event, isWatchEvent(ChangeType.ADD, "added.txt"));