Reverts a regression added recently that blocked the challenge events.
Fixes another potential nul-pointer dereference bug.
* 421/426 server overload equate to HTTP overload. But do special such that
the credentials are asked of the browser on retries.
* 43x and 53x FTP status are all credentials failures of various types.
Other failures are not credential related.
This leaves the other non-credential errors as general failures.
projects / thirdparty / squid.git / commit
