Disable fullscreen exit UI when kiosk mode is on

User should not be able to use the fullscreen exit UI to exit kiosk mode.
This CL disables the UI when kiosk mode is on.

Bug: 867309
Change-Id: Id823d7ec27d416495893170329e2d9c5776efd88
Reviewed-on: https://chromium-review.googlesource.com/1150607
Reviewed-by: Robert Liao <robliao@chromium.org>
Commit-Queue: Yuwei Huang <yuweih@chromium.org>
Cr-Commit-Position: refs/heads/master@{#578040}
1 file changed