Unxfail cc tests

Please merge this once bug 889635 is resolved. (I'm attaching this condition so that we don't have to unxfail and immediately xfail with another bug).

https://bugzilla.mozilla.org/show_bug.cgi?id=889635

`master` -> Don't merge, master is affected by yet another bug but that may be resolved by the time this is ready!
`v1-train` -> Merge