[gnome-tweak-tool] Use ngettext in settings revert warning

[Robert Roth <robertroth src gnome org>]

commit d2085e45c6a1a51dea17e18c9524af8386f79216
Author: Robert Roth <robert roth off gmail com>
Date:   Wed Jan 7 19:21:14 2015 +0200

    Use ngettext in settings revert warning
    
    https://bugzilla.gnome.org/show_bug.cgi?id=742491

 gtweak/tweaks/tweak_group_windows.py |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)
---
diff --git a/gtweak/tweaks/tweak_group_windows.py b/gtweak/tweaks/tweak_group_windows.py
index eb94a09..40dc54b 100644
--- a/gtweak/tweaks/tweak_group_windows.py
+++ b/gtweak/tweaks/tweak_group_windows.py
@@ -20,6 +20,7 @@ from gtweak.gshellwrapper import GnomeShellFactory
 from gtweak.tweakmodel import TWEAK_GROUP_WINDOWS, Tweak
 from gtweak.widgets import ListBoxTweakGroup, GSettingsComboEnumTweak, GSettingsComboTweak, 
GSettingsSwitchTweak, Title, GSettingsSwitchTweakValue, build_label_beside_widget
 from gtweak.utils import XSettingsOverrides
+import gettext
 
 from gi.repository import Gtk, GLib
 
@@ -77,9 +78,15 @@ class WindowScalingFactorTweak(Gtk.Box, Tweak):
             self._dialog.response(Gtk.ResponseType.NO)
             return False
 
+        self._update_countdown_message()
         self._dialog.format_secondary_text(self._second_message % self._countdown)
         return True
 
+    def _update_countdown_message(self):
+        self._second_message = gettext.ngettext(_("Settings will be reverted in %d second"),
+                                                _("Settings will be reverted in %d seconds"),
+                                                self._countdown);
+
     def _close(self):
         if self._source > 0:
             GLib.Source.remove(self._source)
@@ -93,7 +100,7 @@ class WindowScalingFactorTweak(Gtk.Box, Tweak):
         self._countdown = 20
 
         first_message = _("Do you want to keep these HiDPI settings?")
-        self._second_message = _("Settings will be reverted in %d seconds")
+        self._update_countdown_message()
 
         self._dialog = Gtk.MessageDialog(
                                transient_for=self.main_window,