* lib/webrick/server.rb (initialize): Initialize shutdown pipe here
  to avoid race condition.
  (cleanup_shutdown_pipe): New private method.
  (cleanup_listener): Extracted from shutdown method.
  Call this method from start method to avoid race condition.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48353 b2dd03c8-39d4-4d8f-98ff-823fe69b080e