Make asBroadcastStream take two callbacks.

sdk/lib/_internal/pub/test/error_group_test.dart

Index: sdk/lib/_internal/pub/test/error_group_test.dart
diff --git a/sdk/lib/_internal/pub/test/error_group_test.dart b/sdk/lib/_internal/pub/test/error_group_test.dart
index 8fbd0320c2a9335e53d259c534bd26b5f422239b..a5433bdd4d5e9aa43659c0fa3e92237e53020b77 100644
--- a/sdk/lib/_internal/pub/test/error_group_test.dart
+++ b/sdk/lib/_internal/pub/test/error_group_test.dart
@@ -207,8 +207,8 @@ main() {
 
     setUp(() {
       errorGroup = new ErrorGroup();
-      controller = new StreamController(sync: true);
-      stream = errorGroup.registerStream(controller.stream.asBroadcastStream());
+      controller = new StreamController.broadcast(sync: true);
+      stream = errorGroup.registerStream(controller.stream);
     });
 
     test('should pass through values from the stream', () {
@@ -328,10 +328,10 @@ main() {
 
     setUp(() {
       errorGroup = new ErrorGroup();
-      controller1 = new StreamController(sync: true);
-      controller2 = new StreamController(sync: true);
-      stream1 = errorGroup.registerStream(controller1.stream.asBroadcastStream());
-      stream2 = errorGroup.registerStream(controller2.stream.asBroadcastStream());
+      controller1 = new StreamController.broadcast(sync: true);
+      controller2 = new StreamController.broadcast(sync: true);
+      stream1 = errorGroup.registerStream(controller1.stream);
+      stream2 = errorGroup.registerStream(controller2.stream);
     });
 
     test("should pipe exceptions from one stream to the other and to .done",
@@ -387,8 +387,8 @@ main() {
 
     setUp(() {
       errorGroup = new ErrorGroup();
-      controller = new StreamController(sync: true);
-      stream = errorGroup.registerStream(controller.stream.asBroadcastStream());
+      controller = new StreamController.broadcast(sync: true);
+      stream = errorGroup.registerStream(controller.stream);
       completer = new Completer();
       future = errorGroup.registerFuture(completer.future);
     });