In all cases where the record owner of real estate in this state has heretofore conveyed the same, or any part thereof, by express reference in the instrument of such conveyance to a plat of such real estate on file in the office of the county recorder in the county in which such real estate is situated, and a plat so referred to in said conveyance is actually of record in such recorder’s office at the time when such conveyance is made, such record owner and all persons claiming under such record owner, shall be forever estopped from questioning the validity of such plat, notwithstanding that at the time of the execution and record thereof, title to the premises covered thereby, appears of record to have been in the name of a person other than the person who executed such plat as proprietor of the premises covered thereby, and notwithstanding any irregularity or informality in the execution, acceptance, or record of such plat. In all such cases such plat shall be deemed and taken to be valid, confirmed, and legalized in all respects as if actually executed and recorded by the persons who appear of record to have been the owners of the premises covered thereby at the time of the execution and record thereof.