[gnome-terminal/gnome-3-18] window: Exit early from screen-removed handler for now empty notebook

[Christian Persch <chpe src gnome org>]

commit 44c6df308a2e5c331b44797c8537da430bb92df7
Author: Christian Persch <chpe gnome org>
Date:   Sat Sep 19 16:58:34 2015 +0200

    window: Exit early from screen-removed handler for now empty notebook
    
    When the notebook is now empty, it's not necessary to change anything else
    since the window will be closed right away. Since GtkNotebook doesn't send
    the switch-page signal when removing the last and only screen in the notebook,
    priv->active_tab will point to an already freed object, which causes a
    crash when the window tries to update itself for the new active tab.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=755240
    (cherry picked from commit c8704ba3fef98d4acd59ec061566ff540b77c528)

 src/terminal-window.c |   20 +++++++++++++++-----
 1 files changed, 15 insertions(+), 5 deletions(-)
---
diff --git a/src/terminal-window.c b/src/terminal-window.c
index e065ac1..9127966 100644
--- a/src/terminal-window.c
+++ b/src/terminal-window.c
@@ -3468,10 +3468,24 @@ mdi_screen_removed_cb (TerminalMdiContainer *container,
                                         G_CALLBACK (screen_close_cb),
                                         window);
 
+  /* We already got a switch-page signal whose handler sets the active tab to the
+   * new active tab, unless this screen was the only one in the notebook, so
+   * priv->active_tab is valid here.
+   */
+
+  pages = terminal_mdi_container_get_n_screens (container);
+  if (pages == 0)
+    {
+      priv->active_screen = NULL;
+
+      /* That was the last tab in the window; close it. */
+      gtk_widget_destroy (GTK_WIDGET (window));
+      return;
+    }
+
   terminal_window_update_tabs_menu_sensitivity (window);
   terminal_window_update_search_sensitivity (screen, window);
 
-  pages = terminal_mdi_container_get_n_screens (container);
   if (pages == 1)
     {
       TerminalScreen *active_screen = terminal_mdi_container_get_active_screen (container);
@@ -3479,10 +3493,6 @@ mdi_screen_removed_cb (TerminalMdiContainer *container,
 
       terminal_window_update_size (window);
     }
-  else if (pages == 0)
-    {
-      gtk_widget_destroy (GTK_WIDGET (window));
-    }
 }
 
 gboolean