Bug 899236 - [Lockscreen] Reintroduce camera button for...

... passcode input screen

You can see below a screenshot of the passcode input screen with the current patch applied that aims to illustrate that there is no regression for the testcase highlighted in [bug 875271](https://bugzilla.mozilla.org/show_bug.cgi?id=875271) -- the bug which previously removed the camera button to solve the text label issue

![2013-08-16-23-41-19](https://f.cloud.github.com/assets/2195601/973216/68233d2a-061d-11e3-8d03-185ef32b944a.png)