Merge pull request #13893 from asutherland/fix-mail-drafts-test

Bug 938649 - [email] Intermittent Travis Marionette JS Failure: go to local drafts page should show correct name in a item of mail list: NoSuchElement: (7) Unable to locate element: .card-compose .cmp-back-btn. r=lightsofapollo
(cherry picked from commit d4b9aa58bd7c5febb6eb4127e67e54d2a11ec796)