This mainly modifies the stream scheduler to add a weighted fair queuing
algorithm in addition to its round robin algorithm. The WFQ algorithm is
selected whenever interleaving is enabled, to ensure that the socket
stays backwards compatible in the normal (non-interleaved) scenario.
Adaptation to send queue and socket comes in a follow-up CL.
Bug: webrtc:5696
Change-Id: I8f0dbfa8c2f40f2e84cee536ea821e7ef4af6310
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/261947
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37330}
e39f1b5907