In AccessibilityRenderObject::stringValue, m_renderer WeakPtr can become null after the initial null check
<rdar://problem/99103326>
rdar://97946005
Created attachment 461845 [details] Patch
Committed 253778@main (3bdb8087e595): <https://commits.webkit.org/253778@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 461845 [details].