Merge pull request #755 from dart-lang/wa-31963
Prepare for fix of https://github.com/dart-lang/sdk/issues/31963
diff --git a/lib/src/runner/hybrid_listener.dart b/lib/src/runner/hybrid_listener.dart
index a8f1678..8dad2ab 100644
--- a/lib/src/runner/hybrid_listener.dart
+++ b/lib/src/runner/hybrid_listener.dart
@@ -14,8 +14,8 @@
/// A sink transformer that wraps data and error events so that errors can be
/// decoded after being JSON-serialized.
-final _transformer =
- new StreamSinkTransformer.fromHandlers(handleData: (data, sink) {
+final _transformer = new StreamSinkTransformer<dynamic, dynamic>.fromHandlers(
+ handleData: (data, sink) {
ensureJsonEncodable(data);
sink.add({"type": "data", "data": data});
}, handleError: (error, stackTrace, sink) {
