Fix marking changes after a single triage has gone through.
Fix marking changes after a single triage has gone through.

Bug introduced in group triage CL.

BUG=skia:
TBR=stephana

Review URL: https://codereview.chromium.org/943893005

google/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot,google/skia-buildbot,Tiger66639/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot,google/skia-buildbot,Tiger66639/skia-buildbot