Eval'ing breaks stack traces

[devinrhode2]

Over at TraceKit.js we're trying to get some unit testing going: occ/TraceKit#11 (comment)

The key comment from @airportyh there:

Alright, so I had a go with testling and had high hopes for it, because it is really cool how all it requires is for your test framework to output the tap protocol via console.log, so I used Jasmine with the tap reporter. However, ultimately it didn't work for TraceKit because it bundles all of the source code into a string to be executed via eval, which kills stacktraces for TraceKit. I tried instead to hotlink to github for all the source files, but only to realize we are now block by the single-origin policy.

[ljharb]

This doesn't seem actionable, but if I'm wrong, I'm happy to reopen.