Traffic meter: Selectable summary timeout [2/2]

Change-Id: I4f6f1c0fdfd52881b2805b9a5ed4049cdd7caaf4

Thanks to Der-Schubi

commit: https://github.com/temasek/android_packages_apps_Settings/commit/6550106ae6d83c3360552ad9a79c6aaf29bab75f