[gnome-control-center] keyboard: Fix another memory leak

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit eed74317c41de82405795de180e37f45423b424b
Author: Florian Müllner <fmuellner gnome org>
Date:   Fri Jun 30 18:06:52 2017 +0200

    keyboard: Fix another memory leak
    
    The memory leak fixed in commit 870fb462019 is still present in
    a copy-pasted version of the function, apply the same fix there
    as well ...
    
    https://bugzilla.gnome.org/show_bug.cgi?id=784356

 panels/keyboard/cc-keyboard-item.c |   12 +++++++++---
 1 files changed, 9 insertions(+), 3 deletions(-)
---
diff --git a/panels/keyboard/cc-keyboard-item.c b/panels/keyboard/cc-keyboard-item.c
index 619474c..d6f9938 100644
--- a/panels/keyboard/cc-keyboard-item.c
+++ b/panels/keyboard/cc-keyboard-item.c
@@ -63,12 +63,18 @@ G_DEFINE_TYPE (CcKeyboardItem, cc_keyboard_item, G_TYPE_OBJECT)
 static const gchar *
 get_binding_from_variant (GVariant *variant)
 {
+  const char *str, **strv;
+
   if (g_variant_is_of_type (variant, G_VARIANT_TYPE_STRING))
     return g_variant_get_string (variant, NULL);
-  else if (g_variant_is_of_type (variant, G_VARIANT_TYPE_STRING_ARRAY))
-    return g_variant_get_strv (variant, NULL)[0];
-  else
+  else if (!g_variant_is_of_type (variant, G_VARIANT_TYPE_STRING_ARRAY))
     return "";
+
+  strv = g_variant_get_strv (variant, NULL);
+  str = strv[0];
+  g_free (strv);
+
+  return str;
 }
 
 static gboolean