All acts and proceedings heretofore taken under this part by or on behalf of the state or any other public agency for inclusion of its employees in the federal system and all modifications to the agreement executed by the board pursuant to such acts and proceedings are hereby confirmed, validated and declared legally effective. This provision shall operate to supply such legislative authorization as may be necessary to validate such acts, proceedings, and modifications based thereon as the Legislature could have provided for inclusion of such employees in the federal system.