Feedback can include lost packets. Ensure FeedbackGenerator support lost packets to be able to use this class properly when testing with loss. Bug: none Change-Id: Ibd740dfae358c0543fbee62cd40ef13a7ac1123f Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/247372 Reviewed-by: Erik Språng <sprang@webrtc.org> Commit-Queue: Per Kjellander <perkj@webrtc.org> Cr-Commit-Position: refs/heads/main@{#35740}