[gnome-robots] Add some missing const keywords

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 3b34c17221c74a9d37f922906ac48722c81f90c9
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Sat Jun 21 11:42:05 2014 -0500

    Add some missing const keywords

 src/properties.c |    6 +++---
 src/properties.h |    4 ++--
 2 files changed, 5 insertions(+), 5 deletions(-)
---
diff --git a/src/properties.c b/src/properties.c
index 4f2e61e..c694a9b 100644
--- a/src/properties.c
+++ b/src/properties.c
@@ -76,7 +76,7 @@ struct _GnobotsProperties {
   GdkRGBA bgcolour;
   gint selected_config;
   guint keys[N_KEYS];
-  gchar *themename;
+  const gchar *themename;
 };
 /**********************************************************************/
 
@@ -353,7 +353,7 @@ bg_color_callback (GtkWidget * widget, gpointer data)
   conf_set_background_color (&properties.bgcolour);
 }
 
-gchar *
+const gchar *
 properties_theme_name (void)
 {
   return properties.themename;
@@ -602,7 +602,7 @@ load_keys (void)
 }
 
 void
-conf_set_theme (gchar * value)
+conf_set_theme (const gchar * value)
 {
   g_settings_set_string (settings, KEY_THEME, value);
 }
diff --git a/src/properties.h b/src/properties.h
index 5411f25..aeceadf 100644
--- a/src/properties.h
+++ b/src/properties.h
@@ -13,9 +13,9 @@ gboolean properties_sound (void);
 gboolean properties_splats (void);
 gboolean properties_show_toolbar (void);
 gboolean properties_set_config (gint);
-gchar *properties_theme_name (void);
+const gchar *properties_theme_name (void);
 
-void conf_set_theme (gchar * value);
+void conf_set_theme (const gchar * value);
 void conf_set_configuration (gchar * value);
 void conf_set_control_key (gint i, guint keyval);
 void conf_set_enable_sound (gboolean value);