Merge branch 'printing-portal-fix-master' into 'master'

Remember to call print_cb even if print operation is cancelled.

Closes #2917

See merge request GNOME/gtk!2211

gtk/gtkprintoperation-portal.c

@@ -427,7 +427,15 @@ prepare_print_response (GDBusConnection *connection,
       g_free (filename);
     }
   else
-    portal->result = GTK_PRINT_OPERATION_RESULT_CANCEL;
+    {
+      portal->result = GTK_PRINT_OPERATION_RESULT_CANCEL;
+
+      if (portal->print_cb)
+        portal->print_cb (portal->op, portal->parent, portal->do_print, portal->result);
+
+      if (portal->destroy)
+        portal->destroy (portal);
+    }
 
   if (options)
     g_variant_unref (options);