1. r462591 broke presubmit_scheme_histograms.py and
presubmit_bad_message_reasons.py for ~3 weeks (luckily they were broken in an easily noticable way - failing presubits for any edit that touched the protected file).

2. I see that failures in PRESUBMIT_test.py do not block landing a CL via CQ - see https://codereview.chromium.org/2852503002

EXPECTED BEHAVIOR: PRESUBMIT_test.py tests are run automatically by the CQ
 

1. r462591 broke presubmit_scheme_histograms.py and
presubmit_bad_message_reasons.py for ~3 weeks (luckily they were broken in an easily noticable way - failing presubits for any edit that touched the protected file).

2. I see that failures in PRESUBMIT_test.py do not block landing a CL via CQ - see https://codereview.chromium.org/2852503002

EXPECTED BEHAVIOR:
1. PRESUBMIT_test.py tests are run automatically by the CQ.
2. All presubmit checks have a corresponding test.