Add a deletion helper view for clearing space.

This view provides an interface which allows users to clear out
apps and other data which they may no longer need to alleviate
storage pressure. This implementation gives the bits to uninstall
apps which have not been used within the last 60 days from the
system.

A future patch will add in the ability to extend the deletion helper
view to have additional clearing types.

Change-Id: I65cba54ca247d52227e67e2fa9b84fe63fb8ab34
(cherry picked from commit a671272b)