Fix #5501: multicol test linking to self as reference

[gsnedders]

The reference here is pulled from presto-testo (from revision b5d5d519321bb6da4bc825f92c3f4e84db31be6f).

Fixes #5501.

---

This change is 

[ghost]

Build PASSED

Started: 2017-09-25 11:15:34
Finished: 2017-09-25 11:25:51

View more information about this build on:

• WPT PR Status
• TravisCI

[frivoal]

Not super happy with the original test having neither assertion nor comments saying anything about what it's trying to test, nor with the dead code it has, but the new ref looks fine, and isn't guilty for the sins of its father, so to speak. Approving.

[gsnedders]

Yeah, I'm just glad I found a ref for it in presto-testo, means I don't need to figure out what the rendering should be. :)

[rachelandrew]

I'm hoping to find time to do a review of the state of the multicol test suite as part of my work on the spec. So feel free to raise issues and add me to them.

[frivoal]

@rachelandrew You're a saint. I started two stub bugs about issues found in this test. I'm sure there's many more with the same problems, but this gives us a place to start collecting the issues:
#7469
#7470