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Unlike Windows and Linux, Mac allows top UI to show or hide in browser
fullscreen mode. Also this option can be toggled at runtime to make the
change. But in tab fullscreen mode, top UI should always hide. These
require propagating fullscreen and user preference changes, recording
the toolbar styles and applying the layout accordingly.

This CL makes sure the top chrome UI status is correct across different
fullscreen modes, and responds to user changes as well. Some tests are
also added.

BUG=851261,831219,852779
TEST=Pls check the toolbar/tabstrip show or hide correctly when
entering and exiting various fullscreen modes. Bookmark bar, slide-down
menu and traffic lights will be fixed later.

Change-Id: I78a2b68821d5e633ac5c2823f65390809a57dad5
Reviewed-on: https://chromium-review.googlesource.com/1102026
Commit-Queue: Wei Li <weili@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Reviewed-by: Sarah Chan <spqchan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#569301}