GitLab

Delete the Enterprise.ExistingInstallAttributesLock UMA histogram. It's
expired a while ago and doesn't seem to be needed anymore.

Bug: 1084091
Change-Id: Ie62a2f3edae5d1084f0747ef0dc2e19f9c337d0b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2548625
Auto-Submit: Maksim Ivanov <emaxx@chromium.org>
Reviewed-by: Igor <igorcov@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Mark Pearson <mpearson@chromium.org>
Commit-Queue: Mark Pearson <mpearson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#831965}