LearnBoost/engine.io-client — pull request #281 by 3rd-Eden (2014-04-03 15:04:19+00:00)
Title: [fix] new XMLHttpRequest always returns an object

The `XMLHttpRequest` is a function that **might** return an XHR or ActiveX object. As it's invoked using `new XMLHttpRequest` it will always return an object and it will never be null. So doing a for the `open` method should ensure that the correct transport is used.