diff --git a/quic/test_tools/simple_session_notifier.h b/quic/test_tools/simple_session_notifier.h
index 25c9941..aab3769 100644
--- a/quic/test_tools/simple_session_notifier.h
+++ b/quic/test_tools/simple_session_notifier.h
@@ -73,6 +73,7 @@
                         TransmissionType type) override;
   bool IsFrameOutstanding(const QuicFrame& frame) const override;
   bool HasUnackedCryptoData() const override;
+  bool HasUnackedStreamData() const override;
 
  private:
   struct StreamState {