Add structured sort data to ContentResolver.query.

Update DocumentsProvider to override
    ContentProvider#query(Uri, String[], Bundle, CancellationSignal);
Added an otherwise unneeded import to pass doc check
    on DocumentsProvider.

Bug: 30927484
Change-Id: I295c21f53901d567455286f22439f21d22a8a25a
Test: Build and run. Test from DocsUi.