[file-roller] ignore clipboard and actions if they are null

[Paolo Bacchilega <paobac src gnome org>]

commit 67d2081f9b1f54b44304bd7b3db9777cdcce1b44
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Sun Mar 3 09:39:40 2019 +0100

    ignore clipboard and actions if they are null
    
    should mitigate https://gitlab.gnome.org/GNOME/file-roller/issues/31

 src/fr-window.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/src/fr-window.c b/src/fr-window.c
index 35ae8646..efa343bc 100644
--- a/src/fr-window.c
+++ b/src/fr-window.c
@@ -688,7 +688,8 @@ fr_window_enable_action (FrWindow   *window,
        GAction *action;
 
        action = g_action_map_lookup_action (G_ACTION_MAP (window), action_name);
-       g_object_set (action, "enabled", enabled, NULL);
+       if (action != NULL)
+               g_object_set (action, "enabled", enabled, NULL);
 }
 
 
@@ -700,7 +701,8 @@ fr_window_set_action_state (FrWindow   *window,
        GAction *action;
 
        action = g_action_map_lookup_action (G_ACTION_MAP (window), action_name);
-       g_simple_action_set_state (G_SIMPLE_ACTION (action), g_variant_new_boolean (active));
+       if (action != NULL)
+               g_simple_action_set_state (G_SIMPLE_ACTION (action), g_variant_new_boolean (active));
 }
 
 
@@ -741,6 +743,9 @@ fr_window_update_paste_command_sensitivity (FrWindow     *window,
 
        if (clipboard == NULL)
                clipboard = gtk_widget_get_clipboard (GTK_WIDGET (window), _fr_window_get_clipboard_name 
(window));
+       if (clipboard == NULL)
+               return;
+
        running    = window->priv->activity_ref > 0;
        no_archive = (window->archive == NULL) || ! window->priv->archive_present;
        ro         = ! no_archive && window->archive->read_only;