§ 189. Time extended for payment of percentage based on gross receipts. Every corporation building or operating a street surface railroad, or a branch or extension thereof, under the provisions of this article, or chapter two hundred and fifty-two of the laws of eighteen hundred and eighty-four, which, at any time during the period of six years prior to January first, nineteen hundred and one, became liable to pay any percentage based upon the gross receipts of said corporation, under the provisions of section one hundred and seventy-five of this article, and which heretofore has paid or hereafter shall pay, separately or together, the amount of such percentage and, in addition thereto, interest thereon at the rate of seven per centum per annum, computed from the time such percentage became due by said section one hundred and seventy-five up to the time such percentage was or shall be paid, by virtue of such payment or payments, shall be discharged of liability with the same force and effect as if the amount of such percentage had been paid upon the date when it first became due under the provisions of the said section of this article.