This commit fixes the issue of H26xPacketBuffer not supporting the RTP padding packet. Bug: webrtc:383841353 Change-Id: Ibd87cd9c18577d990fa56a2fdfed1552d33b58a2 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/371840 Reviewed-by: Sergey Silkin <ssilkin@webrtc.org> Reviewed-by: Erik Språng <sprang@webrtc.org> Commit-Queue: Sergey Silkin <ssilkin@webrtc.org> Cr-Commit-Position: refs/heads/main@{#43586}