This creates the API for an ICE transport object, and lets it
be accessible from a DTLS transport object.
Bug: chromium:907849
Change-Id: Ieb24570217dec75ce0deca8420739c1f116fbba4
Reviewed-on: https://webrtc-review.googlesource.com/c/118703
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Fredrik Solenberg <solenberg@webrtc.org>
Reviewed-by: Steve Anton <steveanton@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26472}
