Use drain over toList when values are ignored (dart-lang/sse#52)

pkgs/sse/test/sse_test.dart

diff --git a/pkgs/sse/test/sse_test.dart b/pkgs/sse/test/sse_test.dart
index 5fc898c..578b0b7 100644
--- a/pkgs/sse/test/sse_test.dart
+++ b/pkgs/sse/test/sse_test.dart
@@ -74,7 +74,7 @@
       for (var i = 0; i < limit; i++) {
         connection.sink.add('$i');
       }
-      await connection.stream.take(limit).toList();
+      await connection.stream.take(limit).drain();
     });
 
     test('messages arrive in-order', () async {
@@ -147,7 +147,7 @@
       await closeButton.click();
 
       // Should complete since the connection is closed.
-      await connection.stream.toList();
+      await connection.stream.drain();
       expect(handler.numberOfClients, 0);
     });