We'll need to implement this for both Views and Mac

@ellyjones, could you do this for Mac?

Yeah, I can. I'll grab this bug for now.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/142058a0c172ba2260fde35aded4749bd346decd

commit 142058a0c172ba2260fde35aded4749bd346decd
Author: Elly Fong-Jones <ellyjones@chromium.org>
Date: Mon Jun 26 13:42:14 2017

cocoa: mark bookmark bar buttons as popup menu buttons

They behave more like popup menu buttons than plain buttons.

BUG= 735607 

Change-Id: I60c8b5f6a8c625f029887044802e498d5343a08b
Reviewed-on: https://chromium-review.googlesource.com/546295
Commit-Queue: Elly Fong-Jones <ellyjones@chromium.org>
Reviewed-by: Leonard Grey <lgrey@chromium.org>
Cr-Commit-Position: refs/heads/master@{#482257}
[modify] https://crrev.com/142058a0c172ba2260fde35aded4749bd346decd/chrome/browser/ui/cocoa/bookmarks/bookmark_button_cell.mm

dmazzoni: done for mac I think - over to you :)

Views already had "has pop up" set on the bookmark folders in the bookmarks view, and I confirmed it works with ChromeVox. I'll throw up a change to give it a role description of "Folder", but that's optional.

We can expose expandable/expanded state, and fire the state change event when it is collapsed/expanded.

This issue has been Available for over a year. If it's no longer important or seems unlikely to be fixed, please consider closing it out. If it is important, please re-triage the issue.

Sorry for the inconvenience if the bug really should have been left as Available.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Mac triage: to pbos@ for Views a11y :)

Thanks. I've put it on our backlog (added a sticky to our board). +cc dfried@ FYI.

Currently, I'm experiencing the following behavior:
 - bookmarks are read as "[bookmark title] button"
 - folders are read as "[folder name] menu button sub-menu"

This appears to meet the minimum requirements for this issue without having to rework the bookmarks bar. I don't love it, but I'm not sure this is still an accessibility issue. Was there additional work we wanted to tackle on this?

I'm going to mark this one as "fixed" because the request was to differentiate between bookmarks and folders and that's happening. Please verify that the current behavior is acceptable.