[metacity] group: select for property notifies on group leaders

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 953d77dac3f4bd195c5c07f27f169918d9114cee
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Sat Jun 27 00:52:25 2015 -0700

    group: select for property notifies on group leaders

 src/core/group.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/src/core/group.c b/src/core/group.c
index 66aee17..9280384 100644
--- a/src/core/group.c
+++ b/src/core/group.c
@@ -31,6 +31,7 @@ meta_group_new (MetaDisplay *display,
                 Window       group_leader)
 {
   MetaGroup *group;
+  XWindowAttributes attrs;
 #define N_INITIAL_PROPS 3
   Atom initial_props[N_INITIAL_PROPS];
   int i;
@@ -44,6 +45,10 @@ meta_group_new (MetaDisplay *display,
   group->group_leader = group_leader;
   group->refcount = 1; /* owned by caller, hash table has only weak ref */
 
+  XGetWindowAttributes (display->xdisplay, group_leader, &attrs);
+  XSelectInput (display->xdisplay, group_leader,
+                attrs.your_event_mask | PropertyChangeMask);
+
   if (display->groups_by_leader == NULL)
     display->groups_by_leader = g_hash_table_new (meta_unsigned_long_hash,
                                                   meta_unsigned_long_equal);