Bug 816260 - Hotspot Settings: No error message is displayed when Wi-Fi hotspot SSID is blank

Fixed [Bug 816260] Hotspot Settings: No error message is displayed when Wi-Fi hotspot SSID is blank
 https://bugzilla.mozilla.org/show_bug.cgi?id=816260

An error message is displayed and changes are reverted.

![Screenshot from 2013-02-24 02:15:12](https://f.cloud.github.com/assets/1485255/188591/fca1d238-7df9-11e2-89d6-6a938a2f1e6f.png)