bind domain only for async flow

Author: sidorares

lib/Pool.js

@@ -20,9 +20,6 @@ function Pool(options) {
 
 Pool.prototype.getConnection = function (cb) {
 
-  if (cb && process.domain)
-    cb = process.domain.bind(cb);
-
   if (this._closed) {
     return process.nextTick(function(){
       return cb(new Error('Pool is closed.'));
@@ -67,6 +64,8 @@ Pool.prototype.getConnection = function (cb) {
     return cb(new Error('Queue limit reached.'));
   }
 
+  if (cb && process.domain)
+    cb = process.domain.bind(cb);
   this._connectionQueue.push(cb);
 };