Fix race condition in indexer test
Fix race condition in indexer test

Bug: skia:
Change-Id: I5e38f28e07a64945ccc8b130216bc5689d374477
Reviewed-on: https://skia-review.googlesource.com/119960
Reviewed-by: Ben Wagner <3ef7217be91069877d94f7907ce5479000772cd3@google.com>
Commit-Queue: Stephan Altmueller <43343ec95731c0e8daa7359daf7f2f3935582b24@google.com>

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