[autofill] add plumbing for ARIA label and description

This CL integrates ARIA label and description parsing into the render/JS
to browser communication path. This allows the browser to have knowledge
of the ARIA label and description.

Bug: 896719
Change-Id: If5e8d9389f10beecae102080ebcde066aae6c80a
Reviewed-on: https://chromium-review.googlesource.com/c/1342673
Reviewed-by: Moe Ahmadi <mahmadi@chromium.org>
Reviewed-by: Vadym Doroshenko <dvadym@chromium.org>
Reviewed-by: Sebastien Seguin-Gagnon <sebsg@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Reviewed-by: Olivier Robin <olivierrobin@chromium.org>
Commit-Queue: Roger McFarlane <rogerm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#611564}
10 files changed