Add DBus API to determine if a disk should be auto-mountable.

BUG=chromium-os:15000
TEST=Test on a Cr48

Change-Id: Ia956ec4dfbb1579bc88ce054426d8b9c2623758c
Reviewed-on: http://gerrit.chromium.org/gerrit/772
Reviewed-by: Zelidrag Hornung <zelidrag@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
8 files changed