Allow GetInfo on current directory.

But don't allow on Recents (since we can't get info about the root directory).
Allow displayName to be overridden by Intent.EXTRA_TITLE extra.
    This is useful as most root documents don't appear to have useful displayNames.
    So for all root docs, we pass the root name as the title.
Bonus: load directory icon correctly (wasn't being animated to full opacity).

Bug: 64025130
Bug: 64000934
Bug: 64068972
Test: Update menu manager tests. Increased coverage of InspectorController. Added showInspector test coverage.
Change-Id: Ifa125a7e7376aea40b1c53c18ebf5a5d528b440e