merge from trunk:

  *) Fix issue which could cause piped loggers to be orphaned and never
     terminate after a graceful restart.  PR 40651.  [Joe Orton,
     Ruediger Pluem]

Reviewed by: trawick, wrowe


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@483967 13f79535-47bb-0310-9956-ffa450edef68