If the packets are ordered by their ack time, their send
time can decrease in the case they have been reordered.
Bug: webrtc:8415
Change-Id: Ic9fca8d47de37b931085aeefcd62bbddd8869db9
Reviewed-on: https://webrtc-review.googlesource.com/72003
Commit-Queue: Sebastian Jansson <srte@webrtc.org>
Reviewed-by: Philip Eliasson <philipel@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22999}