libwnck: update

News claim it's important for Xfce-4.10, which still builds.

pkgs/development/libraries/libwnck/default.nix

···
-{stdenv, fetchurl, pkgconfig, libX11, gtk, intltool}:
+{ stdenv, fetchurl, pkgconfig, gtk, intltool, xorg }:
 
-stdenv.mkDerivation {
-  name = "libwnck-2.30.7";
+let
+  ver_maj = "2.31";
+  ver_min = "0";
+in
+stdenv.mkDerivation rec {
+  name = "libwnck-${ver_maj}.${ver_min}";
 
   src = fetchurl {
-    url = mirror://gnome/sources/libwnck/2.30/libwnck-2.30.7.tar.xz;
-    sha256 = "15713yl0f8f3p99jzqqfmbicrdswd3vwpx7r3bkf1bgh6d9lvs4b";
+    url = "mirror://gnome/sources/libwnck/${ver_maj}/${name}.tar.xz";
+    sha256 = "17isfjvrzgj5znld2a7zsk9vd39q9wnsysnw5jr8iz410z935xw3";
   };
 
-  buildInputs = [ pkgconfig libX11 gtk intltool ];
+  buildInputs = [ pkgconfig gtk intltool xorg.libX11 xorg.libXres ];
+  # ?another optional: startup-notification
 
   configureFlags = [ "--disable-introspection" ]; # not needed anywhere AFAIK
+
+  meta = {
+    description = "A library for creating task lists and pagers";
+    license = stdenv.lib.licenses.lgpl21;
+  };
 }