Judicial
review of any decision of the city council or any commission, board,
officer or agent thereof, may be had pursuant to Section 1094.5 of
the
Code of Civil Procedure only if the petition for writ of mandate
pursuant to said section is filed within the time limit specified
in Section 1094.6 of the
Code of Civil Procedure. Thereafter, all
persons are barred from commencing or prosecuting any such action
or proceeding or asserting any defense of invalidity or unreasonableness
of such decision, proceeding, determinations or actions taken.