This is a reland of 18cf4b67ddc66041d6b114ea15d78eea74d0592b.
Original change's description:
> Base pacer padding in pause state on time since last send.
>
> 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}
Bug: None
Change-Id: I19fc02bc226ad59cb4cbd2a6ef8ac6f47212f834
Reviewed-on: https://webrtc-review.googlesource.com/53080
Commit-Queue: Sebastian Jansson <srte@webrtc.org>
Reviewed-by: Philip Eliasson <philipel@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22138}
a1630f83d0