Remove chrome/browser/ui/exclusive_access/OWNERS.

better for it to just fall generally into code owned by c/b/ui OWNERS.

Rationale: None of the owners have any recent state on this. It is
Change-Id: I06feb262d6ba2df4aab36c85f54785fe3387e636
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2015905Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Reviewed-by: Yuri Wiitala <miu@chromium.org>
Commit-Queue: Yuri Wiitala <miu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#742919}

chrome/browser/ui/exclusive_access/OWNERS

-miu@chromium.org
-
-# COMPONENT: UI>Browser>FullScreen