Merge pull request #9590 from Profpatsch/dm-lid-management

`desktopManagerHandlesLidAndPower default `false`

nixos/modules/services/x11/desktop-managers/README

···
+Each desktop manager should explicitly specify a value for `services.xserver.displayManager.desktopManagerHandlesLidAndPower`.

nixos/modules/services/x11/desktop-managers/e19.nix

···
         waitPID=$!
       '';
     }];
+    services.xserver.displayManager.desktopManagerHandlesLidAndPower = true;
 
     security.setuidPrograms = [ "e19_freqset" ];
 

nixos/modules/services/x11/desktop-managers/kde4.nix

···
             exec ${kde_workspace}/bin/startkde
           '';
       };
+    services.xserver.displayManager.desktopManagerHandlesLidAndPower = true;
 
     security.setuidOwners = singleton
       { program = "kcheckpass";

nixos/modules/services/x11/desktop-managers/kde5.nix

···
       bgSupport = true;
       start = ''exec ${plasma5.plasma-workspace}/bin/startkde;'';
     };
+    services.xserver.displayManager.desktopManagerHandlesLidAndPower = true;
 
     security.setuidOwners = singleton {
       program = "kcheckpass";

nixos/modules/services/x11/desktop-managers/kodi.nix

···
         waitPID=$!
       '';
     }];
+    services.xserver.displayManager.desktopManagerHandlesLidAndPower = true;
 
     environment.systemPackages = [ pkgs.kodi ];
   };
-}
+}

nixos/modules/services/x11/desktop-managers/xfce.nix

···
             exec ${pkgs.stdenv.shell} ${pkgs.xfce.xinitrc}
           '';
       };
+    services.xserver.displayManager.desktopManagerHandlesLidAndPower = true;
 
     environment.systemPackages =
       [ pkgs.gtk # To get GTK+'s themes.

nixos/modules/services/x11/display-managers/default.nix

···
 
       desktopManagerHandlesLidAndPower = mkOption {
         type = types.bool;
-        default = true;
+        default = false;
         description = ''
           Whether the display manager should prevent systemd from handling
           lid and power events. This is normally handled by the desktop