Mark template class RefCountedObject as final.

ortc/ortcrtpreceiveradapter.cc

Index: ortc/ortcrtpreceiveradapter.cc
diff --git a/ortc/ortcrtpreceiveradapter.cc b/ortc/ortcrtpreceiveradapter.cc
index b30f63c515a5c9d7de5b36980c1b453250f21b9a..e5194867a86aa443674ddbaaabfeb828353f50eb 100644
--- a/ortc/ortcrtpreceiveradapter.cc
+++ b/ortc/ortcrtpreceiveradapter.cc
@@ -151,12 +151,12 @@ void OrtcRtpReceiverAdapter::MaybeRecreateInternalReceiver() {
   internal_receiver_ = nullptr;
   switch (kind_) {
     case cricket::MEDIA_TYPE_AUDIO:
-      internal_receiver_ =
-          new AudioRtpReceiver(rtc::CreateRandomUuid(), ssrc,
-                               rtp_transport_controller_->voice_channel());
+      internal_receiver_ = new rtc::RefCountedObject<AudioRtpReceiver>(
+          rtc::CreateRandomUuid(), ssrc,
+          rtp_transport_controller_->voice_channel());
       break;
     case cricket::MEDIA_TYPE_VIDEO:
-      internal_receiver_ = new VideoRtpReceiver(
+      internal_receiver_ = new rtc::RefCountedObject<VideoRtpReceiver>(
           rtc::CreateRandomUuid(), rtp_transport_controller_->worker_thread(),
           ssrc, rtp_transport_controller_->video_channel());
       break;