Save Draft tests are failing

Some of the Save Draft tests are failing, because they try to set a node author while logged in as a user who doesn't have permission to do that. Looks like this was caused by one of the commits in the middle of #1120164: is a separate permission needed?.

This patch should fix it. It needs to be applied after the followup patch on that issue (http://drupal.org/node/1120164#comment-4422862) in order to work.