lua: use var_ToggleBool.

modules/misc/lua/libs/variables.c

@@ -254,16 +254,15 @@ int __vlclua_var_toggle_or_set( lua_State *L, vlc_object_t *p_obj,
     if( lua_gettop( L ) > 1 ) return vlclua_error( L );
 
     if( lua_gettop( L ) == 0 )
-        b_bool = !var_GetBool( p_obj, psz_name );
+        b_bool = var_ToggleBool( p_obj, psz_name );
     else /* lua_gettop( L ) == 1 */
     {
         b_bool = luaL_checkboolean( L, -1 );
         lua_pop( L, 1 );
+        if( b_bool != var_GetBool( p_obj, psz_name ) )
+            var_SetBool( p_obj, psz_name, b_bool );
     }
 
-    if( b_bool != var_GetBool( p_obj, psz_name ) )
-        var_SetBool( p_obj, psz_name, b_bool );
-
     lua_pushboolean( L, b_bool );
     return 1;
 }