I would rather enable this on Scrutinizer rather than having a failed build just for CS issues. This would keep the Travis status focused on actual breakage and lower the contribution gap for newcomers (if a newcomer has a few CS violations, it may be a better experience to merge and fix them ourselves rather than making them fight with Travis to get a green status). It also makes the work of maintainers easier (if we see a read status from Travis, we know that something important is broken, not just missing a space)