[gnome-boxes] Do not forward grab-broken to display

[Marc-Andre Lureau <malureau src gnome org>]

commit ceeeff4533f1f2deeb8019507ba268d7d077265e
Author: Marc-Andrà Lureau <marcandre lureau gmail com>
Date:   Tue May 22 21:15:38 2012 +0200

    Do not forward grab-broken to display
    
    The eventbox may receive this event, but it is not to be
    forwarded to the display widget.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=676591

 src/display-page.vala |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/src/display-page.vala b/src/display-page.vala
index 4267fbc..cea48dd 100644
--- a/src/display-page.vala
+++ b/src/display-page.vala
@@ -104,6 +104,9 @@ private class Boxes.DisplayPage: GLib.Object {
                 }
             }
 
+            if (event.type == EventType.GRAB_BROKEN)
+                return false;
+
             if (event_box.get_child () != null)
                 event_box.get_child ().event (event);