tmcw/big — pull request #40 by commadelimited (2014-05-22 16:45:13+00:00)
Title: Fix firstChild.nodeName error for empty slides (CSS background)

One of the members of our team wanted a background on a slide, but didn't want it to be fullscreen. So he created an empty div and used CSS to apply a tiling background to it:

```

```

This caused an error when Big attempted to check the `firstChild` property of the div (because it was empty).

`Uncaught TypeError: Cannot read property 'nodeName' of null`

So this checks to make sure there IS a firstChild before proceeding.