Well, they can uninstall the application before upgrading it, they don't need a permission!
Of course it does not take permission,
but I intend to turn in modod automatic uninstalling the app before upgrading
Oh, automatic uninstall is not possible in Android, when the user click update on the play store the app replaces the changed data only.
You can tell your users on the play store description to uninstall the old version.