[Files app] A11y - Add aria-label to <cr-menu>

Add aria-label to <cr-menu>s that are used a combo/drop-down menu in
Files app, so Chromevox can read it when it's opened and focused.

Bug: 889153
Change-Id: Ie6882d796ba284831e7e0a7105600ce21b784007
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1534579
Auto-Submit: Luciano Pacheco <lucmult@chromium.org>
Reviewed-by: Alex Danilo <adanilo@chromium.org>
Commit-Queue: Luciano Pacheco <lucmult@chromium.org>
Cr-Commit-Position: refs/heads/master@{#643233}
1 file changed