Keyboard shortcuts always disabled on single keys

[David Pastl]

It is apprently not possible to set single key shortcuts using the "settings->keyboard" panel. All attempts to set a shortcut to a single key (ex F12 for volume up) display "disabled". This is odd, single if a modifier is used ("super", "alt", etc.) they binding will work and display "ctrl - Audio raise volume" (for a mac keyboard) or "ctrl - F12" for regular keyboards.

Audio controls appear to require manual configuration contrary to what the kernel already knows: http://elementaryos.stackexchange.com/questions/7628/loki-media-keys-shortcuts-volume-keys-broken

[Lepsch (lepsch)]

What causes this is the following shortcut validation in src/Pages/Shortcuts/shorcut.vala, method "valid". Anything different from Print key is not valid.

(modifiers == (Gdk.ModifierType) 0 && accel_key != Gdk.Key.Print)