remove firebug errors

* Fixes #996
* Jenkins: http://jenkins.buttonweavers.com:8080/job/buttonmen-cgolubi1/267/

In an ideal world, Jenkins would catch these, but that's beyond my current understanding of our baling-wide-and-duct-tape solution for getting Jenkins to run QUnit.  I looked at it briefly and concluded it wouldn't be a quick fix.  So for now we should just stomp on firebug errors when we see them, and if it lags master a bit for whatever reason, not the end of the world.