Made possible by r56795, this reduces human and byte code size.
* ext/socket/lib/socket.rb (self.ip_sockets_port0,
self.tcp_server_sockets_port0,
self.tcp_server_sockets,
self.udp_server_sockets): use symbol proc
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56867 b2dd03c8-39d4-4d8f-98ff-823fe69b080e