[mutter/wip/carlosg/selection-fixes: 5/8] wayland: Check resource before emitting cancelled event

[Carlos Garnacho <carlosg src gnome org>]

commit 6377324ffcceac241bc5f63009536fea0aa16165
Author: Carlos Garnacho <carlosg gnome org>
Date:   Fri Oct 11 17:47:00 2019 +0200

    wayland: Check resource before emitting cancelled event
    
    If a data source is destroyed we first unset the resource, and try to
    unref unset the related selection source. At this point the only event
    that might be emitted by the internal selection machinery is .cancelled,
    so make sure we avoid it on destroyed sources.
    
    Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/842

 src/wayland/meta-wayland-data-device.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/src/wayland/meta-wayland-data-device.c b/src/wayland/meta-wayland-data-device.c
index 24e97222a..3dfedd959 100644
--- a/src/wayland/meta-wayland-data-device.c
+++ b/src/wayland/meta-wayland-data-device.c
@@ -1369,7 +1369,8 @@ meta_wayland_source_cancel (MetaWaylandDataSource *source)
   MetaWaylandDataSourceWayland *source_wayland =
     META_WAYLAND_DATA_SOURCE_WAYLAND (source);
 
-  wl_data_source_send_cancelled (source_wayland->resource);
+  if (source_wayland->resource)
+    wl_data_source_send_cancelled (source_wayland->resource);
 }
 
 static void
@@ -1464,7 +1465,8 @@ meta_wayland_data_source_primary_cancel (MetaWaylandDataSource *source)
   MetaWaylandDataSourceWayland *source_wayland;
 
   source_wayland = META_WAYLAND_DATA_SOURCE_WAYLAND (source);
-  gtk_primary_selection_source_send_cancelled (source_wayland->resource);
+  if (source_wayland->resource)
+    gtk_primary_selection_source_send_cancelled (source_wayland->resource);
 }
 
 static void