"Add Files" dialog crashes on i386 architecture

Modified Order store GTimeVal.tv_sec[1]. GTimeVal.tv_sec is glong,
but ui file[2] specify size as gint64. Therefore no problem on 64bit,
on the other hand raise SEGV on 32bit by memory address boundary
problem.

Finally invalid address which is index of GtkListStore is passed
to g_strdup() as memory address.

This patch set same size storead size and allocated size.

[1] see calling gtk_list_store_set() at get_folder_content_done_cb()
    in src/fr-file-selector-dialog.c
[2] src/ui/file-selector.ui:296