HTTPCORE-379: shut down non-blocking server side connection in case of an i/o or runtime error to avoid an infinite loop in the i/o reactor trying to flush buffered output
Contributed by Dmitry Potapov <potapov.d at gmail.com>

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpcore/branches/4.3.x@1590620 13f79535-47bb-0310-9956-ffa450edef68