Get the pub oauth2 test passing locally.

pkg/http/lib/src/utils.dart

Index: pkg/http/lib/src/utils.dart
diff --git a/pkg/http/lib/src/utils.dart b/pkg/http/lib/src/utils.dart
index c61733ef0c6f1b342ffa7eca0410443c1a8d056e..a70e9370058b744f7efc11c221b19d7cd6f7e161 100644
--- a/pkg/http/lib/src/utils.dart
+++ b/pkg/http/lib/src/utils.dart
@@ -309,3 +309,16 @@ Future forEachFuture(Iterable input, Future fn(element)) {
   }
   return nextElement(null);
 }
+
+// TODO(nweiz): remove this when issue 8310 is fixed.
+/// Returns a [Stream] identical to [stream], but piped through a new
+/// [StreamController]. This exists to work around issue 8310.
+Stream wrapStream(Stream stream) {
+  var controller = stream.isBroadcast
+      ? new StreamController.broadcast()
+      : new StreamController();
+  stream.listen(controller.add,
+      onError: (e) => controller.signalError(e),
+      onDone: controller.close);
+  return controller.stream;
+}