GitLab

Both enable-chrome-duet and enable-chrome-duet-labels have been expired
for a while, and have no references anywhere else.

Change-Id: Ic73397dcb831d5472172a31af7384738abdc81bb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2415236Reviewed-by: Matthew Jones <mdjones@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#807992}