When computing the timeouts for keepalives and write completion,

get the current time _after_ processing the event that led to the
timeout, rather than before.
[forward-port of commit 349189 from the async-read-dev branch]


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@349190 13f79535-47bb-0310-9956-ffa450edef68