Hide tab switcher button instead of removing in HTS

Previously the tab switcher button was removed when HTS was enabled.
This is incorrect since accessibility mode could mean reverting to using
the old tab switcher top toolbar with the tab switcher button. This CL
hides and shows the tab switcher button depending on the accessibility
state.

Bug: 914858

Change-Id: I1b74f5ed2e94380e260d2a4c6f0fb746f270e2e5
Reviewed-on: https://chromium-review.googlesource.com/c/1385126
Commit-Queue: Pedro Amaral <amaralp@chromium.org>
Reviewed-by: Theresa <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#619848}
1 file changed