GitLab

Since M60, vibrate always requires user gesture.

Remove the feature flag and M59's deprecation message.

BUG=704650

Change-Id: Ifd1bda521e320fb7c0e8b3378117553e18cad833
Reviewed-on: https://chromium-review.googlesource.com/892581Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Bryan McQuade <bmcquade@chromium.org>
Commit-Queue: Eric Willigers <ericwilligers@chromium.org>
Cr-Commit-Position: refs/heads/master@{#541750}