Update Accessibility docs.

NOTRY=true

Change-Id: Idb932de14ca3eb79a1be1b175f19db48bf51fc07
Reviewed-on: https://chromium-review.googlesource.com/685413
Commit-Queue: Katie Dektar <katydek@google.com>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#504694}
2 files changed