Add visualization of late feedback packets, and avoid plotting incorrect delays computed based on those.

BUG=None

Review-Url: https://codereview.webrtc.org/3009823002
Cr-Original-Commit-Position: refs/heads/master@{#19705}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: a0a8ed78c3f89751d1589c1d66ad61d2b9f7e562
1 file changed