Gardening: Mark a test as flaky
Gardening: Mark a test as flaky

virtual/threaded/transitions/transition-end-event-multiple-01.html
is flaky on Win release as well as debug.

BUG=248938
TBR=gavinp@chromium.org

Review URL: https://codereview.chromium.org/139853026

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@165789 bbb929c8-8fbe-4397-9dbb-9b2b20218538

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