Use QuicSession::transport_version() instead of QuicConnection::transport_version() to make code cleaner.

gfe-relnote: code cleanup, not protected.
PiperOrigin-RevId: 267628510
Change-Id: I2b28c42ec2345870905e7e5d7e88721be86ad6e4
diff --git a/quic/qbone/qbone_client_session.cc b/quic/qbone/qbone_client_session.cc
index c2972ea..5c199e2 100644
--- a/quic/qbone/qbone_client_session.cc
+++ b/quic/qbone/qbone_client_session.cc
@@ -39,8 +39,7 @@
       ->CryptoConnect();
   // Register the reserved control stream.
   QuicStreamId next_id = GetNextOutgoingBidirectionalStreamId();
-  DCHECK_EQ(next_id, QboneConstants::GetControlStreamId(
-                         connection()->transport_version()));
+  DCHECK_EQ(next_id, QboneConstants::GetControlStreamId(transport_version()));
   auto control_stream =
       QuicMakeUnique<QboneClientControlStream>(this, handler_);
   control_stream_ = control_stream.get();