GitLab

In order to use the WebVitalMetrics class with shared memory in the
follow up CLs, make the WebVitalMetrics class trivially copyable.

R=sadrul

Bug: 1151343
Change-Id: Ib613198bfc0b54667b4048ab9e2eefe16b4fbdf6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2602383Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Reviewed-by: David Bokan <bokan@chromium.org>
Reviewed-by: weiliangc <weiliangc@chromium.org>
Commit-Queue: weiliangc <weiliangc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#841635}