Use existing logic in list.js to correctly set aria-activedescandant for the file list.

This means that each file row will be spoken as it is selected.

BUG=151471


Review URL: https://chromiumcodereview.appspot.com/10991033

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@158786 0039d316-1c4b-4281-b951-d872f2087c98
1 file changed