Per MediaSource spec, when calling SourceBuffer.appendBuffer eviction can occurs during the prepare append algorithm [1] If eviction occurs at this time, a `bufferedchange` event should be fired on the SourceBuffer object. [1] https://w3c.github.io/media-source/#dfn-prepare-append
<rdar://problem/106168510>
Pull request: https://github.com/WebKit/WebKit/pull/11095
Committed 261263@main (b76e6ffa9afd): <https://commits.webkit.org/261263@main> Reviewed commits have been landed. Closing PR #11095 and removing active labels.