Conditionalize QUIC client support of requesting server padding.

It should only be tried when the boringssl api version is new enough.
OSS QUICHE's boringssl dependency is currently too old to support this.

PiperOrigin-RevId: 919782728

quiche/quic/core/tls_client_handshaker.cc

diff --git a/quiche/quic/core/tls_client_handshaker.cc b/quiche/quic/core/tls_client_handshaker.cc
index 39c3dba..298ffb0 100644
--- a/quiche/quic/core/tls_client_handshaker.cc
+++ b/quiche/quic/core/tls_client_handshaker.cc
@@ -188,10 +188,12 @@
     }
   }
 
+#if BORINGSSL_API_VERSION >= 41
   if (tls_connection_.ssl_config().server_padding_to_request.has_value()) {
     SSL_set_server_padding_request(
         ssl(), tls_connection_.ssl_config().server_padding_to_request.value());
   }
+#endif
 
   // The compliance policy must be the last thing configured before the
   // handshake in order to have defined behavior.
@@ -638,7 +640,9 @@
     }
   }
 
+#if BORINGSSL_API_VERSION >= 41
   server_sent_padding_ = SSL_server_sent_requested_padding(ssl());
+#endif
 
   state_ = HANDSHAKE_COMPLETE;
   handshaker_delegate()->OnTlsHandshakeComplete();