[mutter] configure.ac: Bump libmutter API version to 3

[Jonas Ådahl <jadahl src gnome org>]

commit 15fa7816bd010a4d651218b17db2c4cb497240cc
Author: Jonas Ådahl <jadahl gmail com>
Date:   Wed Apr 25 15:38:45 2018 +0200

    configure.ac: Bump libmutter API version to 3

 configure.ac | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/configure.ac b/configure.ac
index bfc005180..1a2d5a510 100644
--- a/configure.ac
+++ b/configure.ac
@@ -9,7 +9,7 @@ m4_define([mutter_version],
 
 m4_define([mutter_plugin_api_version], [3])
 
-m4_define([libmutter_api_version], [2])
+m4_define([libmutter_api_version], [3])
 
 AC_INIT([mutter], [mutter_version],
         [http://bugzilla.gnome.org/enter_bug.cgi?product=mutter])