Judges learned in the law of any court of record holding commissions in force at the adoption of this Constitution shall hold their respective offices until the expiration of the terms for which they were commissioned, and until their successors shall be duly qualified. The Governor shall commission the president judge of the court of first criminal jurisdiction for the counties of Schuylkill, Lebanon and Dauphin as a judge of the court of common pleas of Schuylkill county, for the unexpired term of his office.