This UI element is no longer in the mocks. It complicated the
implementation of the fragment because it was causing the wrong
apps to be selected on-tap.
This specific StorageUseActivity usage only happens when coming
from the Storage Settings UI, so we can freely remove it without
harming other uses of ManageApplications.
Bug: 34195303
Test: Manual -- it seemed a bit silly to add a test to ensure that
a broken UI element was indeed missing.
Change-Id: I5396364c297026a33b54d1794d9ad2c5102f0d7f