Android: Close gesture navigation sheet upon tab closure

Navigation Sheet should be closed when its Tab is closed. In most cases
the sheet is close prior to Tab, but the opposite can happen if incognito
tabs are closed via Android notification. This CL ensures the sheet gets
closed upon tab closure.

Bug: 1011073
Change-Id: Id9729c2d8987bfe37ff81f47a8070d40a86e00e7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1842134
Reviewed-by: Matthew Jones <mdjones@chromium.org>
Reviewed-by: Theresa  <twellington@chromium.org>
Commit-Queue: Jinsuk Kim <jinsukkim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#704483}
4 files changed