[mutter] Bump version to 3.21.90

[Florian Müllner <fmuellner src gnome org>]

commit ea08ed7dc4fb954601125d5db3704a927fc950d3
Author: Florian Müllner <fmuellner gnome org>
Date:   Fri Aug 19 12:41:06 2016 +0200

    Bump version to 3.21.90
    
    Update NEWS.

 NEWS         |   21 +++++++++++++++++++++
 configure.ac |    2 +-
 2 files changed, 22 insertions(+), 1 deletions(-)
---
diff --git a/NEWS b/NEWS
index 070c8c3..6c7a0b2 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,24 @@
+3.21.90
+=======
+* Consider XDG_SESSION_TYPE when determining session type [Jouke; #759388]
+* Re-add support for edge scrolling on some touchpads [Bastien; #768245]
+* Support mouse and trackball acceleration profile [Jonas; #769179]
+* Draw monitor contentn to individual framebuffer [Jonas; #768976]
+* Support virtual input devices [Jonas, Carlos; #765009]
+* Set correct output scale on hotplug [Jonas; #769505]
+* Misc. bug fixes and cleanups [Florian, Jonas, Thomas, Bastien, Carlos;
+  #769014, #769024, #769054, #769070, #769036, #769305, #769578, #769800,
+  #769073]
+
+Contributors:
+  Jonas Ådahl, Carlos Garnacho, Thomas Hindoe Paaboel Andersen, Simon McVittie,
+  Alberts Muktupāvels, Florian Müllner, Bastien Nocera, Jouke Witteveen
+
+Translations:
+  Daniel Mustieles [es], Aurimas Černius [lt], Dušan Kazik [sk],
+  Fabio Tomat [fur], Balázs Úr [hu], Yosef Or Boczko [he], Marek Černocký [cs],
+  Matej Urbančič [sl]
+
 3.21.4
 ======
 * Fix missing frame border around GTK+ dialogs [Florian; #745060]
diff --git a/configure.ac b/configure.ac
index df36620..81c1b5b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2,7 +2,7 @@ AC_PREREQ(2.62)
 
 m4_define([mutter_major_version], [3])
 m4_define([mutter_minor_version], [21])
-m4_define([mutter_micro_version], [4])
+m4_define([mutter_micro_version], [90])
 
 m4_define([mutter_version],
           [mutter_major_version.mutter_minor_version.mutter_micro_version])