gfe-relnote: Add NET_EXPORT_PRIVATE and override for Chromium merge. Not protected.

PiperOrigin-RevId: 253279256
Change-Id: I7a2306193b3bf87c1399040b7bfcd641a11af16f
diff --git a/quic/core/crypto/tls_client_connection.h b/quic/core/crypto/tls_client_connection.h
index c741389..a9212ff 100644
--- a/quic/core/crypto/tls_client_connection.h
+++ b/quic/core/crypto/tls_client_connection.h
@@ -11,7 +11,7 @@
 
 // TlsClientConnection receives calls for client-specific BoringSSL callbacks
 // and calls its Delegate for the implementation of those callbacks.
-class TlsClientConnection : public TlsConnection {
+class QUIC_EXPORT_PRIVATE TlsClientConnection : public TlsConnection {
  public:
   // A TlsClientConnection::Delegate implements the client-specific methods that
   // are set as callbacks for an SSL object.