This currently only exists as a goog legacy stat and has no spec equivalent according to https://docs.google.com/document/d/1z-D4SngG36WPiMuRvWeTMN7mWQXrf1XKZwVl3Nf1BIE/edit Yet it is useful to debug issues sometimes. Exposing it as a nonstandard stat will make it show up in chrome://webrtc-internals, removing a need to switch to the legacy stats API there. BUG=webrtc:14118 Change-Id: I506357ad54ff33df3ba46fb81558aa32187ac8e9 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/264420 Commit-Queue: Henrik Boström <hbos@webrtc.org> Reviewed-by: Henrik Boström <hbos@webrtc.org> Cr-Commit-Position: refs/heads/main@{#37055}