Pursuant to the provisions of § 2 of Article XI-E of the Constitution of Maryland, requiring the General Assembly to group the several municipal corporations in this State into not more than four classes based upon population, the General Assembly hereby declares that there is one class of such municipal corporations. Every municipal corporation in this State, as defined by § 9 above, shall be taken and considered as a member of that class, and as subject to the constitutional and statutory laws applicable thereto.