Comment 2 for bug 837307

StacktraceTop:
 gdk_device_get_type () at /build/buildd/gtk+3.0-3.1.12/./gdk/gdkdevice.c:76
 _gtk_widget_get_device_window (widget=0x8d8e1f8, device=0x8a87008) at /build/buildd/gtk+3.0-3.1.12/./gtk/gtkwidget.c:10957
 gtk_grab_notify_foreach (child=0x8d8e1f8, data=0xbf565384) at /build/buildd/gtk+3.0-3.1.12/./gtk/gtkmain.c:2117
 gtk_box_forall (container=0x8d6fc60, include_internals=1, callback=0xade9f0 <gtk_grab_notify_foreach>, callback_data=0xbf565384) at /build/buildd/gtk+3.0-3.1.12/./gtk/gtkbox.c:1844
 gtk_container_forall (container=0x8d6fc60, callback=0xade9f0 <gtk_grab_notify_foreach>, callback_data=0xbf565384) at /build/buildd/gtk+3.0-3.1.12/./gtk/gtkcontainer.c:2032