Nixpkgs: Not possible to use multiple layouts in services.xserver.layout

[rickynils]

cc @aszlig

Issue description

Not possible to use multiple layouts in services.xserver.layout:

building path(s) ‘/nix/store/zliji90zqz5rc8rfl19ya7qp9nyn7r4b-xkb-layouts-exist’

The selected keyboard layout definition does not exist:

  de,us

Set `services.xserver.layout' to the name of an existing keyboard
layout (check /nix/store/5nidmghgw700wkj4pycg9a80q25qbxzb-xkeyboard-config-2.21/etc/X11/xkb/rules/base.lst for options).

This is possible in the release-17.03 master, and also advertised in the option description: https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/services/x11/xserver.nix#L298

Steps to reproduce

Set the NixOS option services.xserver.layout to a comma-separated list of layouts (like us,se)

Technical details

• Nixpkgs version: master (a6cf6367e2abd9610da804286cc6c439d79717db)

[themoritz]

Can confirm, same here