We shouldn't need to flush on creation, and can just wait until we have a need.
<rdar://problem/113657395>
Pull request: https://github.com/WebKit/WebKit/pull/16541
Committed 266883@main (2f426da28a3b): <https://commits.webkit.org/266883@main> Reviewed commits have been landed. Closing PR #16541 and removing active labels.