[gnome-shell] Update Mutter minimum version for plugin changes

[Owen Taylor <otaylor src gnome org>]

commit 6873539846f4c87a48dc214ea58ee289452942eb
Author: Owen W. Taylor <otaylor fishsoup net>
Date:   Fri Jun 25 16:27:28 2010 -0400

    Update Mutter minimum version for plugin changes
    
    Require mutter-2.31.4, which has the revised effects plugin API.

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 863f751..5363132 100644
--- a/configure.ac
+++ b/configure.ac
@@ -60,7 +60,7 @@ AM_CONDITIONAL(BUILD_RECORDER, $build_recorder)
 CLUTTER_MIN_VERSION=1.2.8
 GOBJECT_INTROSPECTION_MIN_VERSION=0.6.11
 GJS_MIN_VERSION=0.7
-MUTTER_MIN_VERSION=2.31.2
+MUTTER_MIN_VERSION=2.31.4
 GTK_MIN_VERSION=2.18.0
 GIO_MIN_VERSION=2.25.9