[perf] Minor code optimizations (#2219)

Author: tabone

lib/index.js

@@ -382,16 +382,17 @@ var emitterMethods = Object.keys(Emitter.prototype).filter(function(key){
 
 emitterMethods.concat(['to', 'in', 'use', 'send', 'write', 'clients', 'compress']).forEach(function(fn){
   Server.prototype[fn] = function(){
-    var nsp = this.sockets[fn];
-    return nsp.apply(this.sockets, arguments);
+    return this.sockets[fn].apply(this.sockets, arguments);
   };
 });
 
 Namespace.flags.forEach(function(flag){
-  Server.prototype.__defineGetter__(flag, function(){
-    this.sockets.flags = this.sockets.flags || {};
-    this.sockets.flags[flag] = true;
-    return this;
+  Object.defineProperty(Server.prototype, flag, {
+    get: function() {
+      this.sockets.flags = this.sockets.flags || {};
+      this.sockets.flags[flag] = true;
+      return this;
+    }
   });
 });
 

lib/namespace.js

@@ -69,10 +69,12 @@ Namespace.prototype.__proto__ = Emitter.prototype;
  */
 
 exports.flags.forEach(function(flag){
-  Namespace.prototype.__defineGetter__(flag, function(){
-    this.flags = this.flags || {};
-    this.flags[flag] = true;
-    return this;
+  Object.defineProperty(Namespace.prototype, flag, {
+    get: function() {
+      this.flags = this.flags || {};
+      this.flags[flag] = true;
+      return this;
+    }
   });
 });
 
@@ -137,7 +139,7 @@ Namespace.prototype.run = function(socket, fn){
  */
 
 Namespace.prototype.to =
-Namespace.prototype['in'] = function(name){
+Namespace.prototype.in = function(name){
   this.rooms = this.rooms || [];
   if (!~this.rooms.indexOf(name)) this.rooms.push(name);
   return this;

lib/socket.js

@@ -83,10 +83,12 @@ Socket.prototype.__proto__ = Emitter.prototype;
  */
 
 flags.forEach(function(flag){
-  Socket.prototype.__defineGetter__(flag, function(){
-    this.flags = this.flags || {};
-    this.flags[flag] = true;
-    return this;
+  Object.defineProperty(Socket.prototype, flag, {
+    get: function() {
+      this.flags = this.flags || {};
+      this.flags[flag] = true;
+      return this;
+    }
   });
 });
 
@@ -96,8 +98,10 @@ flags.forEach(function(flag){
  * @api public
  */
 
-Socket.prototype.__defineGetter__('request', function(){
-  return this.conn.request;
+Object.defineProperty(Socket.prototype, 'request', {
+  get: function() {
+    return this.conn.request;
+  }
 });
 
 /**