Use more smart pointers in Element.cpp
Created attachment 458486 [details] Patch
Committed r293569 (250083@main): <https://commits.webkit.org/250083@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 458486 [details].
<rdar://problem/92445797>
*** Bug 234172 has been marked as a duplicate of this bug. ***