All acknowledgments, affidavits, or other notarial acts, heretofore taken or performed by notaries public of this state, who were at the same time justices of the peace, otherwise in conformity with the requirements of the law, shall be valid to all intents and purposes, as if the same had been taken or performed by notaries public of this commonwealth who were not, at the same time, justices of the peace: Provided, however, That no case heretofore judicially decided or now pending shall be affected by this act.