Bug 1037054 - FxOS Loop client app bits for bug 1016277

See bug https://bugzilla.mozilla.org/show_bug.cgi?id=1037054 please.
Because they wont be the same reference:
>       _onmozinterruptbegin = _fireEvent.bind(null, 'mozinterruptbegin');
>       _ac.addEventListener('mozinterruptbegin', _onmozinterruptbegin);
>       _onmozinterruptend = _fireEvent.bind(null, 'mozinterruptend');
>       _ac.addEventListener('mozinterruptend', _onmozinterruptend);