Chrome Version       : 54.0.2840.98
OS Version: OS X 10.11.6
URLs (if applicable) :
Other browsers tested:
  Add OK or FAIL after other browsers where you have tested this issue:
     Safari 5:
  Firefox 4.x:
     IE 7/8/9:

What steps will reproduce the problem?
1. Shift-tab to move focus to an element that has aria-describedby set.
2. Note what is announced by ChromeVox.

What is the expected result?
The aria-describedby element gets announced aloud consistently, whether you are tabbing forward or backward.

What happens instead of that?
The aria label gets read but not its associated aria-describedby. When tabbing forward (ie just "Tab"), the aria-describedby does get used.

Please provide any additional information below. Attach a screenshot if
possible.

This does not repro in ChromeVox Next.

UserAgentString: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.98 Safari/537.36