Missing keyboard navigation in dock context menus or search results

[DavidBriscoe]

While I can see Unity being great on a tablet, I rely on my computer's keyboard.

There's already an issue for a keyboard shortcut to invoke search (bug 644425), but Unity also needs keyboard navigation in the dock context menus (go up and down to select items) and in search results to provide better accessibility. (Note that while Enter successfully launches the first search result, but there's no apparent way to select another result or to browse the results.)