dotcloud/docker — pull request #6059 by erikh (2014-05-27 19:35:45+00:00)
Title: Fix race condition in CLI tests: diff was not acquiring a container lock

The diff tests in the CLI could execute before the container started, ending up in a diff that contains some of the metadata docker peppers in the container on start.

This adds a lock around the changes job which conflicts with the lock in Start() and thusly avoids this issue.