test [nfc]: Make addStreams async

This is the next step toward making handleEvent async.

Author: gnprice

test/model/internal_link_test.dart

@@ -17,7 +17,7 @@ Future<PerAccountStore> setupStore({
   final account = eg.selfAccount.copyWith(realmUrl: realmUrl);
   final store = eg.store(account: account);
   if (streams != null) {
-    store.addStreams(streams);
+    await store.addStreams(streams);
   }
   await store.addUser(eg.selfUser);
   if (users != null) {

test/model/message_list_test.dart

@@ -559,7 +559,7 @@ void main() async {
       final stream1 = eg.stream(streamId: 1, name: 'stream 1');
       final stream2 = eg.stream(streamId: 2, name: 'stream 2');
       await prepare(narrow: const AllMessagesNarrow());
-      store.addStreams([stream1, stream2]);
+      await store.addStreams([stream1, stream2]);
       store.addSubscription(eg.subscription(stream1));
       store.addUserTopic(stream1, 'B', UserTopicVisibilityPolicy.muted);
       store.addSubscription(eg.subscription(stream2, isMuted: true));

test/model/test_store.dart

@@ -125,10 +125,10 @@ extension PerAccountStoreTestExtension on PerAccountStore {
   }
 
   Future<void> addStream(ZulipStream stream) async {
-    addStreams([stream]);
+    await addStreams([stream]);
   }
 
-  void addStreams(List<ZulipStream> streams) {
+  Future<void> addStreams(List<ZulipStream> streams) async {
     handleEvent(StreamCreateEvent(id: 1, streams: streams));
   }
 

test/model/unreads_test.dart

@@ -152,12 +152,12 @@ void main() {
   });
 
   group('count helpers', () {
-    test('countInAllMessagesNarrow', () {
+    test('countInAllMessagesNarrow', () async {
       final stream1 = eg.stream(streamId: 1, name: 'stream 1');
       final stream2 = eg.stream(streamId: 2, name: 'stream 2');
       final stream3 = eg.stream(streamId: 3, name: 'stream 3');
       prepare();
-      streamStore.addStreams([stream1, stream2, stream3]);
+      await streamStore.addStreams([stream1, stream2, stream3]);
       streamStore.addSubscription(eg.subscription(stream1));
       streamStore.addSubscription(eg.subscription(stream2));
       streamStore.addSubscription(eg.subscription(stream3, isMuted: true));

test/widgets/inbox_test.dart

@@ -61,7 +61,7 @@ void main() {
     await testBinding.globalStore.add(eg.selfAccount, eg.initialSnapshot());
     store = await testBinding.globalStore.perAccount(eg.selfAccount.id);
 
-    store.addStreams(streams ?? []);
+    await store.addStreams(streams ?? []);
     store.addSubscriptions(subscriptions ?? []);
     await store.addUsers(users ?? [eg.selfUser]);