* rename
* we don't need underscore to check whether an array is empty
* add types, resolve type issues
* remove unused markTop in run.js
* Make the type a little more consistent
* Tweak a check for an empty array
Co-Authored-By: Marcelo T Prado <marceloterreiroprado@gmail.com>
Because longjohn was collecting frames across runs of self test in the loop, we were actually seeing frame lists that applied to more than one test.
This wasn't actually causing problems except in our frame parsing tests, but you can imagine that it would be quite unhelpful.
