System.Security.PermissionListSet.UpdateArrayList C# (CSharp) Method

        private static void UpdateArrayList(ArrayList current, ArrayList newList)
        {
            if (newList == null)
                return;

            for(int i=0;i < newList.Count; i++)
            {
                if (!current.Contains(newList[i]))
                    current.Add(newList[i]);
            }
        
        }

 // Token: 0x06001D59 RID: 7513 RVA: 0x00065FC4 File Offset: 0x000641C4
 private void UpdateZoneAndOrigin(PermissionListSet pls)
 {
     if (pls != null)
     {
         if (this.m_zoneList == null && pls.m_zoneList != null && pls.m_zoneList.Count > 0)
         {
             this.m_zoneList = new ArrayList();
         }
         PermissionListSet.UpdateArrayList(this.m_zoneList, pls.m_zoneList);
         if (this.m_originList == null && pls.m_originList != null && pls.m_originList.Count > 0)
         {
             this.m_originList = new ArrayList();
         }
         PermissionListSet.UpdateArrayList(this.m_originList, pls.m_originList);
     }
 }