scm: mercurial: add :order => 'id DESC' explicitly for MySQL test fails.
Because :order => 'id DESC' is defined at 'has_many', there is no need to set 'order'. But, MySQL test fails. Sqlite3 and PostgreSQL pass. Is this MySQL bug?
Authored by: tmaruyama 2011-03-11
Parent: [r5090]
Child: [r5092]
