class ActionDispatch::Cookies::NullSerializer

which gives us the opportunity to detect and migrate legacy cookies.
allows us to handle the (de)serialization step within the cookie jar,
Passing the NullSerializer downstream to the Message{Encryptor,Verifier}

def self.dump(value) 

def self.dump(value)
  value
end

def self.load(value) 

def self.load(value)
  value
end