The State shall not be precluded by possession, grant, conveyance or any other cause or title from making inquest and sale of all such lands as have heretofore escheated to the State by the death of the person last seized thereof, any law, custom or usage to the contrary notwithstanding. But no lands claimed under grant or under an actual possession for five years prior to July 4, 1776 shall be affected by this section.