Sample test log below. See more failures on https://ci.chromium.org/p/chromium/builders/luci.chromium.try/win7_chromium_rel_ng?limit=200

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ERROR: testFileDownloadWithClick (__main__.ChromeDownloadDirTest)
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Traceback (most recent call last):
  File "../../chrome/test/chromedriver/test/run_py_tests.py", line 1960, in testFileDownloadWithClick
    driver = self.CreateDriver(download_dir=download_dir)
  File "../../chrome/test/chromedriver/test/run_py_tests.py", line 292, in CreateDriver
    **kwargs)
  File "e:\b\swarm_slave\w\ir\chrome\test\chromedriver\test\..\client\chromedriver.py", line 237, in __init__
    response = self._ExecuteCommand(Command.NEW_SESSION, params)
  File "e:\b\swarm_slave\w\ir\chrome\test\chromedriver\test\..\client\chromedriver.py", line 291, in _ExecuteCommand
    raise _ExceptionForLegacyResponse(response)
SessionNotCreatedException: session not created exception
from tab crashed
  (Session info: chrome=69.0.3477.0)
  (Driver info: chromedriver=2.40.571448 (0666896aa7b7a39661a6bfe3a930e11ce41fc4d2),platform=Windows NT 6.1.7601 SP1 x86_64)

Please take a look and reassign if it's not related to your change. Thanks!