[Merge to M65]cros: Add device end of life message in md about page.

Chrome OS devices receive new feature Stable updates every six weeks,
these updates are for at least five years from the time devices are launched,
after 5 years the new feature updates are no longer guaranteed and devices will
eventually stop receiving updates. At this point, the device will be considered
End of Life.

The about page retrieves the end of life status(supported or end of life) from
update engine and show a message, an end of life icon, as well as an link for
more information: https://www.google.com/chromebook/older/
when status == end of life.

TBR=stevenjb@chromium.org,michaelpg@chromium.org
(cherry picked from commit 32816fa77bef96fdbb306a65352a1f3c1bc91a74)

Bug: 809258
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I18568894a88cb8e1aabdf22613f748eb8bfbf8be
Reviewed-on: https://chromium-review.googlesource.com/936448
Reviewed-by: Michael Giuffrida <michaelpg@chromium.org>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Commit-Queue: Xiaoyin Hu <xiaoyinh@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#539661}
Reviewed-on: https://chromium-review.googlesource.com/941793
Reviewed-by: Xiaoyin Hu <xiaoyinh@chromium.org>
Cr-Commit-Position: refs/branch-heads/3325@{#627}
Cr-Branched-From: bc084a8b5afa3744a74927344e304c02ae54189f-refs/heads/master@{#530369}
15 files changed