This clarifies the logic behind the pacer packet interval in paused state and prepares for future congestion window functionality. Bug: None Change-Id: Ibf6e23f73523b43742830353915b2b94d09a6fc9 Reviewed-on: https://webrtc-review.googlesource.com/52060 Reviewed-by: Stefan Holmer <stefan@webrtc.org> Commit-Queue: Sebastian Jansson <srte@webrtc.org> Cr-Commit-Position: refs/heads/master@{#22004}