This will allow exposing VP8, VP9 and H264-specific RTP header metadata in JavaScript (behind a flag). This information appears to be necessary for cloning (https://github.com/w3c/webrtc-encoded-transform/issues/161), and cloning should be the same as "new frame + setMetadata + setBytes", ergo this should be exposed. Bug: webrtc:14709 Change-Id: Ie71c05f40689bbd529dc4674a07a87c7910b22d5 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/290880 Reviewed-by: Harald Alvestrand <hta@webrtc.org> Commit-Queue: Henrik Boström <hbos@webrtc.org> Cr-Commit-Position: refs/heads/main@{#39101}