[jhbuild] core-deps-3.20: use the gtkmm-3-20 branch of gtkmm

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 0388af702545e88fa99f5c2661f9b58434da56fd
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Tue May 31 12:37:15 2016 +0300

    core-deps-3.20: use the gtkmm-3-20 branch of gtkmm

 modulesets/gnome-suites-core-deps-3.20.modules |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/modulesets/gnome-suites-core-deps-3.20.modules b/modulesets/gnome-suites-core-deps-3.20.modules
index dc9eca4..90e01cb 100644
--- a/modulesets/gnome-suites-core-deps-3.20.modules
+++ b/modulesets/gnome-suites-core-deps-3.20.modules
@@ -681,7 +681,7 @@
   </autotools>
 
  <autotools id="gtkmm">
-    <branch/>
+    <branch revision="gtkmm-3-20"/>
     <dependencies>
       <dep package="cairomm"/>
       <dep package="pangomm"/>