This is the same as the existing version, except it uses the Operations Chain. As such, if an asynchronous operation that uses the chain is currently pending, such as CreateOffer() or CreateAnswer(), AddIceCandidate() will not happen until the previous operation completes. Bug: chromium:1019222 Change-Id: Ie6e5fc386fa9c29b5e2f8e3f65bfbaf9837d351c Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/158741 Commit-Queue: Henrik Boström <hbos@webrtc.org> Reviewed-by: Steve Anton <steveanton@webrtc.org> Cr-Commit-Position: refs/heads/master@{#29704}