Steps to reproduce:
1. In (gnome-control-center) Keyboard settings’ Shortcuts, set the shortcut for ’Lock screen’ to Scroll Lock.
2. Press Scroll Lock.

What happens:
Nothing (screen doesn’t get locked).

What I expect to happen:
For the screen to get locked.

What works:
* Setting ’Lock screen’ shortcut to Shift + Scroll Lock, Ctrl + Scroll Lock etc.
* Setting ’Lock screen’ shortcut to, for example, the Pause/Break key (which is right next to Scroll Lock on common keyboards).
* Setting Scroll Lock as the ’Lock screen’ shortcut in Unity 2D.

Other notes:
Pressing Scroll Lock does nothing whether set as screen locking hotkey or not, so it shouldn’t be tied to some other function either.