Enable a11y extension api browsertest for mash.

Bug: 876043
Change-Id: Ie0300e018c8943e6430b5fe8a8f70d53cd1b4b41
Reviewed-on: https://chromium-review.googlesource.com/c/1407648
Commit-Queue: Scott Violet <sky@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#622316}
2 files changed