[glade] Add a translator comment

[Matthias Clasen <matthiasc src gnome org>]

commit f9c3c32b818fee880d7b506cc1282f95aa93ea2e
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Mar 2 13:27:34 2015 -0500

    Add a translator comment
    
    The wording here is a bit awkward, and it is not obvious
    is "Setting" is a verb or a noun.

 plugins/gtk+/glade-header-bar-editor.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)
---
diff --git a/plugins/gtk+/glade-header-bar-editor.c b/plugins/gtk+/glade-header-bar-editor.c
index 48a7da6..db36388 100644
--- a/plugins/gtk+/glade-header-bar-editor.c
+++ b/plugins/gtk+/glade-header-bar-editor.c
@@ -133,9 +133,15 @@ use_custom_title_toggled (GtkWidget            *widget,
   glade_editable_block (GLADE_EDITABLE (editor));
 
   if (use_custom_title)
+    /* Translators: %s is the name of a widget here, the sentence means:
+     * Make the widget use a custom title
+     */
     glade_command_push_group (_("Setting %s to use a custom title"),
                               glade_widget_get_name (gwidget));
   else
+    /* Translators: %s is the name of a widget here, the sentence means:
+     * Make the widget use the standard title
+     */
     glade_command_push_group (_("Setting %s to use the standard title"),
                               glade_widget_get_name (gwidget));