In all cases in which the county treasurer of any county in the state of Washington shall have executed a tax deed or deeds prior to February 21, 1903, either to his or her county or to any private person or persons or corporation whomsoever, said deed or deeds shall not be deemed invalid by reason of the county treasurer who executed the same not having affixed a seal of office to the same, or having affixed a seal not an official seal; nor shall said deed or deeds be deemed invalid by reason of the fact that at the date of the execution of said deed or deeds there was in the state of Washington no statute providing for an official seal for the office of county treasurer.