Section 49. Any provision of any agreement in effect as of June 24, 2009 between the authority and a freight railroad including, but not limited to, provisions relating to the liability of, or contribution or indemnity by, the authority, shall be interpreted pursuant to chapter 258 as in effect on June 24, 2009, notwithstanding the date of the incident giving rise to the interpretation of any such provision. For the purposes of this section, ''freight railroad'' shall include a person, railroad corporation and any other legal entity in the business of providing freight rail transportation.