WebContent processes that don't have the dynamic-codesigning entitlement shouldn't try to allocate a holding MAP_JIT region
<rdar://problem/88094997>
<rdar://88094922>
Created attachment 450069 [details] Patch
r=me
Committed r288677 (246483@main): <https://commits.webkit.org/246483@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 450069 [details].