[gnome-terminal/gnome-3-18] window: Pass tab switching keys to the terminal for tabless windows

[Debarshi Ray <debarshir src gnome org>]

commit 448cb610ed7c9f243275050b4b3a530561f0f8ab
Author: Debarshi Ray <debarshir gnome org>
Date:   Mon Oct 5 20:13:05 2015 +0200

    window: Pass tab switching keys to the terminal for tabless windows
    
    This was removed as a side effect of
    a319aeb66f36e728af1b4929ddd69574df838702
    
    https://bugzilla.gnome.org/show_bug.cgi?id=730128

 src/terminal-window.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/src/terminal-window.c b/src/terminal-window.c
index 9127966..618425c 100644
--- a/src/terminal-window.c
+++ b/src/terminal-window.c
@@ -1820,6 +1820,7 @@ static void
 terminal_window_update_tabs_menu_sensitivity (TerminalWindow *window)
 {
   TerminalWindowPrivate *priv = window->priv;
+  GAction *gaction;
   GtkActionGroup *action_group = priv->action_group;
   GtkAction *action;
   int num_pages, page_num;
@@ -1856,6 +1857,9 @@ terminal_window_update_tabs_menu_sensitivity (TerminalWindow *window)
   gtk_action_set_sensitive (action, not_last);
 #endif
 
+  gaction = g_action_map_lookup_action (G_ACTION_MAP (window), "switch-tab");
+  g_simple_action_set_enabled (G_SIMPLE_ACTION (gaction), num_pages > 1);
+
   action = gtk_action_group_get_action (action_group, "TabsMoveLeft");
   gtk_action_set_sensitive (action, not_first);
   action = gtk_action_group_get_action (action_group, "TabsMoveRight");