nodejitsu/node-http-proxy — pull request #549 by mmoulton (2014-01-14 07:48:31+00:00)
Title: Only emit response if a valid server is present

When a callback is passed into .web() such as:
```
proxy.web(req, res, function (err) {
// handle error
});
```
the `server` var is set to false and therefor can't emit the `proxyRes`.