Add a new WebContentsAccessibilityTest

Bug: None
Change-Id: Ic63e1619729b79dc5c6010fed3223895c72c5999
Reviewed-on: https://chromium-review.googlesource.com/679446
Commit-Queue: Dominic Mazzoni <dmazzoni@chromium.org>
Reviewed-by: Paul Miller <paulmiller@chromium.org>
Cr-Commit-Position: refs/heads/master@{#559208}
1 file changed