Add missing assignment in RTCConfiguration.mm

Bug: webrtc:9719
Change-Id: Ie18437070c1305df6c52d1a5c2bd3eabe50ea8c6
Reviewed-on: https://webrtc-review.googlesource.com/c/108182
Commit-Queue: Kári Helgason <kthelgason@webrtc.org>
Reviewed-by: Bjorn Mellem <mellem@webrtc.org>
Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25406}
diff --git a/sdk/objc/api/peerconnection/RTCConfiguration.mm b/sdk/objc/api/peerconnection/RTCConfiguration.mm
index 35cdc46..f550a3a 100644
--- a/sdk/objc/api/peerconnection/RTCConfiguration.mm
+++ b/sdk/objc/api/peerconnection/RTCConfiguration.mm
@@ -189,6 +189,7 @@
       _iceConnectionReceivingTimeout;
   nativeConfig->ice_backup_candidate_pair_ping_interval =
       _iceBackupCandidatePairPingInterval;
+  nativeConfig->use_media_transport = _useMediaTransport;
   rtc::KeyType keyType =
       [[self class] nativeEncryptionKeyTypeForKeyType:_keyType];
   if (_certificate != nullptr) {