Include max move distance in layout shift behind a RuntimeEnabledFeature.

This will allow us to enable this feature in M76, in the event that
we don't finish the analysis for this feature until after branch.

Change-Id: I087e4a5e8f5556f5fec16d2e5c9f323c57e581ce
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1627698
Reviewed-by: Steve Kobes <skobes@chromium.org>
Commit-Queue: Bryan McQuade <bmcquade@chromium.org>
Cr-Commit-Position: refs/heads/master@{#663406}
2 files changed