If suit is not brought within 7 years from the return to controvert the decision of the commissioners, or in which the accuracy of the bounds or lines fixed by them is questioned, the record of the return shall be conclusive evidence of the original location of the land, and of the lines and boundaries. If the return shall, in any such suit, be confirmed in any particular by the verdict of a jury, it shall be conclusive to that extent, as between the same parties and those claiming under them, or any of them; saving to infants, and persons mentally ill, imprisoned, or beyond sea, and those claiming under them, the right to bring any such suit, within 5 years from the removal of their disability. The term of 7 years shall not begin to run against any person while that person is in possession of the land in controversy.