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- Exporting of ETW events can be turned on using --trace-export-events-to-etw.

BUG=

Committed: https://crrev.com/1cc86c4f686869f32dfede093a07828c73563892
Cr-Commit-Position: refs/heads/master@{#324982}

Review URL: https://codereview.chromium.org/1038453002

Cr-Commit-Position: refs/heads/master@{#325408}