Add storage allowed categories

Add "Media" and "Media and Files" allowed categories to storage permissions,
based on if the app has scoped storage permissions or not.

Fixes: 144306826
Test: Navigate to the Permission Apps screen for storage (or "Files and
Media"). The apps on the page should be split into "allowed for all
files" and "allowed for media only" categories.

Change-Id: I34a28ab63023c450040b4d272a2e0157fb457849