fix(reporter): Ensure errors use the source map

[brianmhunt]

Closes #1495

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[brianmhunt]

I signed it!

[googlebot]

CLAs look good, thanks!

[brianmhunt]

The CI error being reported is:

1. launchers/base.js restart should start when already finished (crashed):
   Uncaught AssertionError: expected spy to have been called at least once, but it was never called

Which doesn't look like anything I've done, or in any case it's quite beyond me right now how to address it. :)

[dignifiedquire]

Which doesn't look like anything I've done, or in any case it's quite beyond me right now how to address it. :)

Don't worry about it, some of our tests are a bit sensitive to travis :(

[dignifiedquire]

Could you please

• change the commit message to follow our convention please and
• add a test in https://github.com/karma-runner/karma/blob/master/test/unit/reporter.spec.coffee

[brianmhunt]

@dignifiedquire Will do, shortly. Sorry for the oversight. Cheers.

[brianmhunt]

@dignifiedquire Test added (and passing) in 7071d0d; not quite sure if I have the convention renaming down. It may need a rebase, which is beyond me. 😁 If needed, do you mind taking care of the commit naming convention?

Thanks & Cheers

[dignifiedquire]

Thanks, will squash them myself

[dignifiedquire]

Merged as 0407a22