Bug#568930: possible workaround for #568930

[anton a.]

Here's a patch created by linux.org.ru user AptGet (not me, of course). 
It removes "if(!replacement) return;" from str_replace in 
panel-plugin/xfce4-mpc-plugin.c and makes xfce4-mpc-plugin show empty 
space instead of %artist%/%album%/%track%/etc if the corresponding tag 
is not found.
--- a/panel-plugin/xfce4-mpc-plugin.c
+++ b/panel-plugin/xfce4-mpc-plugin.c
@@ -405,8 +405,6 @@ mpc_update_outputs(t_mpc* mpc)
 static void
 str_replace(GString *str, gchar* pattern, gchar* replacement)
 {
-   if (!replacement)
-      return;
    gchar *nstr = exo_str_replace(str->str, pattern, replacement);
    g_string_assign(str, nstr);
    g_free(nstr);