Compatibility detection between MySQL Client and MySQL Server,
in case when server receives X Protocol message which contains
field that it doesn't know. Every field that was defined after
initial release of X Protocol must be tests using:

  Client -> Server: Mysqlx.Expect.Open(+field_exist:field_id)
  Client <- Server: Mysqlx.Ok
  ... client - server message exchange ...
  Client -> Server: Mysqlx.Expect.Close()
  Client <- Server: Mysqlx.Ok

Approved by: Tarique Saleem <tarique.saleem@oracle.com>