message: [InsertableStreams] Save the transformer to be set on Reconfigure.
  Cr-Commit-Position: refs/heads/master@{#30983}
diff: @@ -227,16 +227,15 @@ std::vector<RtpSource> AudioRtpReceiver::GetSources() const {
  void AudioRtpReceiver::SetDepacketizerToDecoderFrameTransformer(
  rtc::scoped_refptr<webrtc::FrameTransformerInterface> frame_transformer) {
  - if (media_channel_ && ssrc_.has_value() && !stopped_) {
  worker_thread_->Invoke<void>(
  - RTC_FROM_HERE,
  - [this, frame_transformer = std::move(frame_transformer)] {
  + RTC_FROM_HERE, [this, frame_transformer = std::move(frame_transformer)] {
  RTC_DCHECK_RUN_ON(worker_thread_);
  frame_transformer_ = frame_transformer;
  + if (media_channel_ && ssrc_.has_value() && !stopped_) {
  media_channel_->SetDepacketizerToDecoderFrameTransformer(
  *ssrc_, frame_transformer);
  - });
  }
  + });
  }
  void AudioRtpReceiver::Reconfigure() {
  