launcher: Replace mutter-launch with logind integration

This uses David Herrmann's new logind sessions interface to retrieve
fds for input devices, rather than using a custom setuid helper to do
the management. This vastly simplifies the interface.

This requires systemd v210, at least.

https://bugzilla.gnome.org/show_bug.cgi?id=724604

src/backends/native/dbus-utils.h

@@ -0,0 +1,32 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
+
+/*
+ * Copyright (C) 2014 Red Hat
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ *
+ * Written by:
+ *     Jasper St. Pierre <jstpierre@mecheye.net>
+ */
+
+#ifndef DBUS_UTILS_H
+#define DBUS_UTILS_H
+
+char *
+get_escaped_dbus_path (const char *prefix,
+                       const char *component);
+
+#endif /* DBUS_UTILS_H */