Added ABS2

Introducing AutomaticBrightnessStrategy2 and making the existing
AutomaticBrightnessStrategy implement the strategy interface. With this
change AutomaticBrightnessStrategy2 is being deprecared. All the changes
happening to AutomaticBrightnessStrategy should be replicated to
AutomaticBrightnessStrategy2 as well.

Bug: 294444204
Test: atest DisplayServicesTest

Change-Id: If26eb988a79f7fe09a24f87eee8bac861794627b