There is no need to iterate through all outstanding data chunks to know
if a FORWARD-TSN can be sent. As the FORWARD-TSN will just move the
cumulative TSN ack, if a chunk is found that is not to be expired,
there is no need to continue any further. This makes it much faster
to know if to send a FORWARD-TSN when the congestion window is large.
Bug: webrtc:12799
Change-Id: I58bce408ae9814c8d3d7bbb480b0037a2cf88dd7
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/219625
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#34176}