Summary: Static code analysis complained `Cannot unset offset 'Authorization'|'Host' on array<int<0, max>, array{string, mixed}>.` Per avivey's look at the code, we only ever get headers in the form of X-Hgargs-* in $headers anyway, so the special-case here won't ever happen. Delete this code. Also see similar code at the bottom of `AphrontHTTPProxyResponse.php`. Test Plan: Read the code. Reviewers: O1 Blessed Committers, avivey Reviewed By: O1 Blessed Committers, avivey Subscribers: avivey, tobiaswiese, valerio.bozzolan, Matthew, Cigaryno Differential Revision: https://we.phorge.it/D25743