xfce: does not explicitly require a gvfs package

- In order to use GIO/GVFS it is enough to enable the gvfs service.

- The module option services.gvfs.package can be used to choose a
  variation of the gvfs package, if desired.

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

@@ -151,7 +151,6 @@ in
     services.upower.enable = config.powerManagement.enable;
     services.gnome3.glib-networking.enable = true;
     services.gvfs.enable = true;
-    services.gvfs.package = pkgs.xfce.gvfs;
     services.tumbler.enable = true;
     services.system-config-printer.enable = (mkIf config.services.printing.enable (mkDefault true));
     services.xserver.libinput.enable = mkDefault true; # used in xfce4-settings-manager

pkgs/desktops/xfce/applications/gigolo/default.nix

@@ -1,4 +1,4 @@
-{ lib, mkXfceDerivation, gtk3, gvfs, glib }:
+{ lib, mkXfceDerivation, gtk3, glib }:
 
 mkXfceDerivation {
   category = "apps";
@@ -8,7 +8,7 @@ mkXfceDerivation {
 
   sha256 = "8UDb4H3zxRKx2y+MRsozQoR3es0fs5ooR/5wBIE11bY=";
 
-  buildInputs = [ gtk3 glib gvfs ];
+  buildInputs = [ gtk3 glib ];
 
   postPatch = ''
     # exo-csource has been dropped from exo

pkgs/desktops/xfce/core/thunar/default.nix

@@ -12,7 +12,6 @@
 , libxslt
 , xfconf
 , gobject-introspection
-, gvfs
 , makeWrapper
 , symlinkJoin
 , thunarPlugins ? []
@@ -35,7 +34,6 @@ let unwrapped = mkXfceDerivation {
     exo
     gdk-pixbuf
     gtk3
-    gvfs
     libX11
     libgudev
     libnotify

pkgs/desktops/xfce/default.nix

@@ -15,9 +15,6 @@ lib.makeScope pkgs.newScope (self: with self; {
 
   automakeAddFlags = pkgs.makeSetupHook { } ./automakeAddFlags.sh;
 
-  # Samba is a rather heavy dependency
-  gvfs = pkgs.gvfs.override { samba = null; };
-
   #### CORE
 
   exo = callPackage ./core/exo { };