```
The dereference (req->evcon->http_server) takes place in
evhttp_parse_request_line and is a consequence of our hacky but
necessary use of the internal function evhttp_parse_firstline_ in the
http_request fuzzing harness.
The suggested workaround is not aesthetically pleasing, but it
successfully avoids the troublesome code path.
" http:// HTTP/1.1\n" was a crashing input prior to this workaround.
```
Backport of core PR19140.
Depends on D9001.