[mutter] wayland: Emit signal on selection data source destruction

[Carlos Garnacho <carlosg src gnome org>]

commit 169f0e7324d481801a96b6daf65f44bc80c54e3d
Author: Carlos Garnacho <carlosg gnome org>
Date:   Wed Mar 2 16:35:03 2016 +0100

    wayland: Emit signal on selection data source destruction
    
    This is necessary for the X11 side to catch up, and unset the selection
    ownership on our window that represents the wayland side in X11 selection.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=760745

 src/wayland/meta-wayland-data-device.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/src/wayland/meta-wayland-data-device.c b/src/wayland/meta-wayland-data-device.c
index 5416054..b06d03d 100644
--- a/src/wayland/meta-wayland-data-device.c
+++ b/src/wayland/meta-wayland-data-device.c
@@ -1117,6 +1117,8 @@ selection_data_source_destroyed (gpointer data, GObject *object_was_here)
       if (data_device_resource)
         wl_data_device_send_selection (data_device_resource, NULL);
     }
+
+  wl_signal_emit (&data_device->selection_ownership_signal, NULL);
 }
 
 static void