Consult HAVE(MACH_PORT_CALAYER_CONTENTS)
<rdar://problem/102831386>
Pull request: https://github.com/WebKit/WebKit/pull/6995
Committed 257257@main (ee0a6a9a3b2b): <https://commits.webkit.org/257257@main> Reviewed commits have been landed. Closing PR #6995 and removing active labels.