For all messages where the last fragment was _not_ put on the wire, the
send queue is responsible for generating lifecycle events, but once all
fragments have been put on the wire, it's the retransmission queue that
is responsible. It does that by marking the final fragment of a message
with the lifecycle identifier, and once that message has been fully
acked by the cumulative ack TSN, it's clear that the peer has fully
received all fragments of the message, as the last fragment was acked.
For abandoned messages - where FORWARD-TSNs are sent, those will be
replied to by a SACK as well, and then we report abandoned messages
separately, to later trigger `OnLifecycleMessageExpired`.
This CL adds support in OutstandingData, which doesn't generate the
callbacks itself, but just reports them in the AckInfo.
Bug: webrtc:5696
Change-Id: I64092f13bcfda685443b7df9967b04d54aedd36a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/264124
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37448}