Added battery level and time to the status tray's accessible name.

Appended already written accessible strings for time and battery to the status tray's current name.
Ensured the dispatched accessibility event for any events coming from the status tray reads the status tray name and not the names of the buttons inside the status tray bar.

BUG= 392666

Review URL: https://codereview.chromium.org/380943002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@284818 0039d316-1c4b-4281-b951-d872f2087c98
9 files changed