Commit f9b592aa27c5a2e184d6cb6ca68d61e8ef4eaba1

Azat Khuzhin 2018-11-23T00:42:46

test: add TT_RETRIABLE for http/cancel_by_host_no_ns Could fail from time to time in travis-ci: https://travis-ci.org/libevent/libevent/jobs/458554097#L1702 Follow-up-for: fe5b0719 ("Mark a lot of flacky tests with TT_RETRIABLE (for linux/win32 only)") (cherry picked from commit 1d2ef90032bc842bc2e295ee4adce3408b6d85da)