perf: Fix tracedb perf trybot ingestion test.
perf: Fix tracedb perf trybot ingestion test.

BUG=skia:
TBR=stephana

Review URL: https://codereview.chromium.org/1488573003

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