It's much faster to use the contents of .git/config to verify if a git checkout is a git-svn checkout.
<rdar://problem/72899735>
Created attachment 417197 [details] Patch
r=me
Committed r271258: <https://trac.webkit.org/changeset/271258> All reviewed patches have been landed. Closing bug and clearing flags on attachment 417197 [details].