Refs #16490 - Add a commit to ensure that a fresh read is provided; this is...

Refs #16490 - Add a commit to ensure that a fresh read is provided; this is only a problem for databases in REPEATABLE READ mode, which is MySQL InnoDB's default. Thanks to Jim Dalton for the report and patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16781 bcc190cf-cafb-0310-a4f2-bffc1f526a37