Discovered earlier today that the current code computes branch-point incorrectly in git checkouts, partially because our Mocking code also computed it incorrectly.
<rdar://problem/71561569>
Created attachment 414512 [details] Patch
Committed r270004: <https://trac.webkit.org/changeset/270004> All reviewed patches have been landed. Closing bug and clearing flags on attachment 414512 [details].