[gthumb] fixed a warning

[Paolo Bacchilega <paobac src gnome org>]

commit 1c117abb1e0eeb05e0d6a4744ec6b59aaddfdce7
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Mon Dec 8 16:18:26 2014 +0100

    fixed a warning

 extensions/image_viewer/preferences.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/extensions/image_viewer/preferences.c b/extensions/image_viewer/preferences.c
index b50d2c6..612dca8 100644
--- a/extensions/image_viewer/preferences.c
+++ b/extensions/image_viewer/preferences.c
@@ -63,7 +63,7 @@ static void
 zoom_quality_radiobutton_toggled_cb (GtkToggleButton *button,
                                     BrowserData     *data)
 {
-       g_settings_set_enum (data->settings, PREF_IMAGE_VIEWER_ZOOM_QUALITY, (button == GET_WIDGET 
("zoom_quality_high_radiobutton")) ? GTH_ZOOM_QUALITY_HIGH : GTH_ZOOM_QUALITY_LOW);
+       g_settings_set_enum (data->settings, PREF_IMAGE_VIEWER_ZOOM_QUALITY, (GTK_WIDGET (button) == 
GET_WIDGET ("zoom_quality_high_radiobutton")) ? GTH_ZOOM_QUALITY_HIGH : GTH_ZOOM_QUALITY_LOW);
 }