see bug 699022 and  bug 698869 . A big problem that made the CQ hosed was that test_installer without the patch was always green, it seems to be not running any tests. See https://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_rel_ng/builds/395963 as an example.

I think until this is fixed, it's better to take the target off the CQ.