[WebRTC] RtpPacketizer::SplitAboutEqually() should return an empty std::vector when payload_len is 0. Currently it returns a std::vector<int> with a single value of 0, which causes various ::NumPackets() methods to incorrectly return 1 instead of 0. <rdar://119058459>
<rdar://119073448>
Pull request: https://github.com/WebKit/WebKit/pull/21210
Committed 271481@main (1838f3eb70b2): <https://commits.webkit.org/271481@main> Reviewed commits have been landed. Closing PR #21210 and removing active labels.