f0ca2dc934
which implements the handshaking logic of the DTLS-STUN piggybacking. Not wired up yet, split from https://webrtc-review.googlesource.com/c/src/+/362480 BUG=webrtc:367395350 Change-Id: I9ee8ff17af4ec96fb891d9852ac50825155735a8 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/370679 Reviewed-by: Harald Alvestrand <hta@webrtc.org> Commit-Queue: Jonas Oreland <jonaso@webrtc.org> Reviewed-by: Jonas Oreland <jonaso@webrtc.org> Cr-Commit-Position: refs/heads/main@{#43606}