[Status Bar Refactor] 3/3: Inject StatusBarWindowView instead of having the

controller construct it.

This will allow us to pass in a fake view for testing the controller.

This CL also moves the window view and controller into its own package
for slightly better organization.

Fixes: 204583449
Test: atest SystemUITests
Test: manual once-over of key user journeys
Change-Id: I4c2cc3f0c3a18466b2d1a1012c999f530329d3f7