* lib/webrick/httpproxy.rb: remvoe useless assigned variables.
* lib/webrick/httpservlet/cgihandler.rb: ditto.
* lib/webrick/httpservlet/erbhandler.rb: ditto.
* lib/webrick/server.rb: ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@46560 b2dd03c8-39d4-4d8f-98ff-823fe69b080e