Move QuicCryptoServerStream::Helper to QuicCryptoServerStreamBase

gfe-relnote: rename class - no behavior change
PiperOrigin-RevId: 296246242
Change-Id: I68425fe4ba7a2040eed4bf93835639e6f353a406
diff --git a/quic/quartc/quartc_crypto_helpers.h b/quic/quartc/quartc_crypto_helpers.h
index 8f0fe96..92c68b6 100644
--- a/quic/quartc/quartc_crypto_helpers.h
+++ b/quic/quartc/quartc_crypto_helpers.h
@@ -99,7 +99,8 @@
 };
 
 // Implementation of the server-side crypto stream helper.
-class QuartcCryptoServerStreamHelper : public QuicCryptoServerStream::Helper {
+class QuartcCryptoServerStreamHelper
+    : public QuicCryptoServerStreamBase::Helper {
  public:
   bool CanAcceptClientHello(const CryptoHandshakeMessage& message,
                             const QuicSocketAddress& client_address,