Auto merge of #17459 - indygreg:backout-testing, r=Manishearth
Auto merge of #17459 - indygreg:backout-testing, r=Manishearth

Servo backout testing

We deployed the Servo VCS backout service recently and want to test it. The goal is to land this PR so it is replicated to the Firefox repo. Then we'll back out this PR from the Firefox repo, which should trigger a new PR against Servo to do the backout.

The changed code is not wrong. So if things don't go as planned, it shouldn't harm anyone.

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