Bug 1015527 - Back/Forward navigation shouldn't break the Translation UI, r=felipe, a=gavin.
Bug 1017560 - Choosing the same language will modify the state of Show Translation button, r=felipe, a=gavin.
Bug 1012535 - Handle translation service unavailable errors, r=felipe, a=gavin.
Bug 1025956 - Missing toolbarbutton-dropdown-arrow@2x.png file - remove the CSS rule, r=Gijs, a=lmandel.