This requires making CallConfig move-only so it can hold a unique_ptr to the factory, but as discussed with Danil, that seems fine. Bug: chromium:355610792 Change-Id: Ie52e33faaa4a2af748daeb25f5327b7a532936e2 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/357862 Reviewed-by: Harald Alvestrand <hta@webrtc.org> Commit-Queue: Tony Herre <herre@google.com> Reviewed-by: Danil Chapovalov <danilchap@webrtc.org> Cr-Commit-Position: refs/heads/main@{#42679}