[refactor] Remove useless self var (#45)

index.js

@@ -164,19 +164,18 @@ Adapter.prototype.clients = function(rooms, fn){
   rooms = rooms || [];
 
   var ids = {};
-  var self = this;
   var sids = [];
   var socket;
 
   if (rooms.length) {
     for (var i = 0; i < rooms.length; i++) {
-      var room = self.rooms[rooms[i]];
+      var room = this.rooms[rooms[i]];
       if (!room) continue;
       var sockets = room.sockets;
       for (var id in sockets) {
         if (sockets.hasOwnProperty(id)) {
           if (ids[id]) continue;
-          socket = self.nsp.connected[id];
+          socket = this.nsp.connected[id];
           if (socket) {
             sids.push(id);
             ids[id] = true;
@@ -185,9 +184,9 @@ Adapter.prototype.clients = function(rooms, fn){
       }
     }
   } else {
-    for (var id in self.sids) {
-      if (self.sids.hasOwnProperty(id)) {
-        socket = self.nsp.connected[id];
+    for (var id in this.sids) {
+      if (this.sids.hasOwnProperty(id)) {
+        socket = this.nsp.connected[id];
         if (socket) sids.push(id);
       }
     }