Fixing Keyboard Navigation to match spec.

Couple known problems still:
- Tabs go to the search/sort/etc icons first, as opposed to the
breadcrumb.
- There's no "focus" indicator for the sort items.

Test: Manually checked, works.

Bug: 32411179
Bug: 34243462
Bug: 31995556
Change-Id: I39240c0bafee9236f5ea5b760eff437739074cd3