Allow attaching/detaching external images (MTLSharedTexture, IOSurface) that can be represented by a MachSendRight.
<rdar://problem/109495127>
Pull request: https://github.com/WebKit/WebKit/pull/14006
Committed 264712@main (891ad78c430b): <https://commits.webkit.org/264712@main> Reviewed commits have been landed. Closing PR #14006 and removing active labels.