I think this line is causing the test failures in Travis.  In order to log the JQuery object, the JS engine needs to recursively serialize each property of the object.  I suspect that Travis has a version of Firefox installed that handles this differently than the version you and I have installed (it passes for me locally too).

When I remove this line, the build passes: https://travis-ci.org/edx/edx-tim/builds/21312674