Tabbing out of search field doesnt remove focus

When I am using the tab key to go through the page & go out of the search box, it doesn't remove the focus style.

cc. @jschatz1 @alfredo1

Reassigned to @iamphill

mentioned in merge request !4704 (merged)

mentioned in commit 77c8600a

Milestone changed to %8.10

Good point @iamphill

Status changed to closed by merge request !4704 (merged)

mentioned in commit c051630a

mentioned in commit 966eedd3

Mentioned in commit stanhu/gitlab-ce@c051630a