For the purposes of this Act and of any other enactment relating to local government or to any of the functions of local authorities, counties shall, subject to any alteration effected by this Act or after the commencement of this Act, have the contents and boundaries which they respectively had immediately before the commencement of this Act for the purposes of the [52 & 53 Vict. c. 50.] Local Government (Scotland) Act, 1889.