The legislative body of any city or village may by ordinance adopt any such precised plat certified to it by the planning commission as provided in section 1: Provided, That notice of time and place when and where it shall be considered for final passage shall be sent by mail to the record owners of land located within or abutting on the new lines of such proposed streets, ways, places, parks, playgrounds or other public grounds or extensions thereof designated on the plat. Any modification of such certified plat before passage of the adopting ordinance, and any amending ordinance originating in the legislative body shall be submitted to the planning commission for its approval: Provided, That in case of disapproval the commission shall communicate its reasons therefor to the legislative body which shall thereafter have the power to overrule such disapproval by a recorded vote of not less than 2/3 of its entire membership. Failure of the planning commission to report on any such modification or amendment within 30 days shall be deemed to constitute an approval thereof. The adoption of any such certified plat by ordinance, or by amending ordinance, shall not in and of itself constitute or be deemed to constitute the opening or establishment of any street or the taking or acceptance of any land for any of the aforesaid purposes.