This prepares for making the BBR implementation more identical to the implementation in Quic, to ensure that results are comparable. Bug: webrtc:8415 Change-Id: Icc66b748e52efb80b5c3ade85f83de6b224a4bd2 Reviewed-on: https://webrtc-review.googlesource.com/76581 Commit-Queue: Sebastian Jansson <srte@webrtc.org> Reviewed-by: Björn Terelius <terelius@webrtc.org> Cr-Commit-Position: refs/heads/master@{#23227}