RenderVideo::videoBox crashes when intrinsic size is zero
<rdar://problem/117755803>
Pull request: https://github.com/WebKit/WebKit/pull/19789
<rdar://problem/116303559>
Committed 270032@main (0dfdb1a30720): <https://commits.webkit.org/270032@main> Reviewed commits have been landed. Closing PR #19789 and removing active labels.