Don't hide content just to remove file inputs (bug 974191)

In order to hide the file inputs on the reviewer page there was an extra &lt;div> which had the side effect of hiding the entire end of the page, including the file inputs, checkboxes, and the submit button. I removed the extraneous div and added a class and a feature test so the file inputs (and *only* the file inputs) should be hidden if there is not filesystem support on the device. Unfortunately, I don't have a device without filesystem support to test on (Unagi, for instance), but have tested that the hidden content is now shown.