git-webkit setup should verify the credentials before saving them. When I run git-webkit setup first time, I entered incorrect credentials (e.g.: email instead of username). git-webkit happily accepted the credentials, and configured incorrect remote based on those incorrect credentials. There should be some kind of validation before saving the credentials to ensure that credentials are correct.
I incorrectly associated 247173@main (r289687) with https://bugs.webkit.org/show_bug.cgi?id=235297, when it really fixed this bug. That change was reverted in 247175@main (r289690) because I had forgotten to cover the not-required case and broke commit queue.
I have re-landed this change in 247283@main (r289835), fixing that problem. Note that verification only happens when the caller requests it, and we only request verification in `git-webkit setup`