1/N Add QSCustomizerController

This CL adds QSCustomizerController for the QSCustomizer, attempting
to remove injection from the view. I originally set out to only
move TileAdapter from the view to its controller, but it grew quickly.

Not all of the injection has been removed from the view but a lot has.

Bug: 168904199
Test: atest SystemUITests && manual.
Change-Id: I5b8ac260e9c74eed4c616a2462d80b2b1f699615