Function webkit_user_content_filter_store_save_from_file 

pub unsafe extern "C" fn webkit_user_content_filter_store_save_from_file(
    store: *mut WebKitUserContentFilterStore,
    identifier: *const c_char,
    file: *mut GFile,
    cancellable: *mut GCancellable,
    callback: GAsyncReadyCallback,
    user_data: gpointer,
)