Fix QUIC warnings in preparation for enabling them

gfe-relnote: n/a, compilation-only change
PiperOrigin-RevId: 253893322
Change-Id: I15917a1c5b325922850086277cfad5e3b4da20a4
diff --git a/quic/quartc/quartc_dispatcher.cc b/quic/quartc/quartc_dispatcher.cc
index 240ddc1..a9d5510 100644
--- a/quic/quartc/quartc_dispatcher.cc
+++ b/quic/quartc/quartc_dispatcher.cc
@@ -53,7 +53,7 @@
 QuartcSession* QuartcDispatcher::CreateQuicSession(
     QuicConnectionId connection_id,
     const QuicSocketAddress& client_address,
-    QuicStringPiece alpn,
+    QuicStringPiece /*alpn*/,
     const ParsedQuicVersion& version) {
   // Make our expected connection ID non-mutable since we have a connection.
   SetShouldUpdateExpectedServerConnectionIdLength(false);