Add support for FloatRoundedRect, IntRect, IntPoint, IntSize, FloatSize, layoutUnit, LayoutPoint, LayoutSize in the new serialization format
<rdar://problem/99863456>
Pull request: https://github.com/WebKit/WebKit/pull/4302
Pull request: https://github.com/WebKit/WebKit/pull/4322
Committed 254724@main (70f24d86a523): <https://commits.webkit.org/254724@main> Reviewed commits have been landed. Closing PR #4322 and removing active labels.