Publish permission based on submitter rather than creator

When a user creates an edition, and another user edits and submits it for 2i, then the original creating user should be allowed to review and publish. 
Rather than just being able to "see" the button, maybe these tests should be about actually being able to perform the action. i.e. "Then I should not be able to publish the publication" and  "Then I should be able to publish the publication...". In the latter case, the step could actually go the whole hog and publish the publication, verifying that it's not just the visibility of the button, but also the ability to complete the action.