Updated documents UX around action bar.

Change action bar to match current design; drawer is always available
and navigation dropdown is used to interact with current traversal
path in hierarchy.  On first launch, show recents with drawer
expanded.  On subsequent launches, resume from last location with
drawer closed.  If last location root isn't applicable, then behave
like initial launch.  Move sort order into action bar submenu.

Delete documents using contract.  Use unstable provider when
inflating DocumentInfo from Uri.

Bug: 10330219, 10510851
Change-Id: I6e94637d70ebca156a6c5d50272e878156d0dd62