Update the BEFORE/SINCE, SYSTEM_VERSION_PREFIX, and MACOSX_DEPLOYMENT_TARGET flags
Created attachment 424313 [details] Patch
<rdar://problem/75861212>
Note that there are important steps to take when updating ANGLE. See https://trac.webkit.org/wiki/UpdatingANGLE
I see at least one problem. Fixing.
Created attachment 424317 [details] Patch
Committed r275082: <https://commits.webkit.org/r275082> All reviewed patches have been landed. Closing bug and clearing flags on attachment 424317 [details].