Used only by test code and by pseudo_tcp. Bug: webrtc:6424 Change-Id: I28903e74f7b69cbdd8c368f4444c8a233eb76868 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/128868 Reviewed-by: Karl Wiberg <kwiberg@webrtc.org> Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org> Commit-Queue: Niels Moller <nisse@webrtc.org> Cr-Commit-Position: refs/heads/master@{#27341}