Processing goal metrics for device type / model / brand was not working properly.
The visitor column value was not available when processing the goal conversion, which should be fixed with this changes.
I've also added some small tests to prove the goal metrics are processed correctly for device type / brand / model.
Failing UI tests seem not to be related to this PR.
LGTM. I'll confirm on demo3 in coming days when the reports work :+1: