Set default wallpaper in Mate

branding.spec

@@ -179,8 +179,9 @@ License: Distributable
 Group: Graphical desktop/GNOME
 Requires: gtk2-theme-mist
 Requires: gksu
+Requires: libgio
 Requires: altlinux-freedesktop-menu-gnomish-menu
-PreReq: gnome-panel
+PreReq:   gnome-panel
 Provides: gnome-theme-%brand-%theme = %version-%release
 Provides: metacity-theme-%brand-%theme = %version-%release
 Provides: metacity-theme
@@ -313,6 +314,7 @@ install -m 644 index.theme '%buildroot/%_datadir/themes/%XdgThemeName/'
 mkdir -p '%buildroot/etc/xdg/menus/'
 install -m 644 gnome-applications.menu '%buildroot/etc/xdg/menus/'
 install -m 644 settings.menu '%buildroot/etc/xdg/menus/'
+install -m 644 50_mate-background.gschema.override '%buildroot%_datadir/glib-2.0/schemas/'
 popd
 
 #slideshow

gnome-settings/50_mate-background.gschema.override

+[org.mate.background]
+color-shading-type="solid"
+primary-color="#0c0c2c2c6c6c"
+picture-options="zoom"
+picture-filename="/usr/share/design/current/backgrounds/default.png"
+secondary-color="#0c0c2c2c6c6c"
+