[Central Surfaces] Replace mWakeUpComingFromTouch with KeyguardRepo.

This removes some CentralSurfaces code by reusing the new `wakefulness`
flow in Keyguard instead of saving this variable in CentralSurfaces.

This *could* introduce some behavior changes:
   mWakeUpComingFromTouch is only set if a class used
   CentralSurfaces#wakeUpIfDozing to wake the device. Now that we're
   using the general wakefulness status, other device wake events that
   didn't go through #wakeUpIfDozing could now also increase the falsing
   threshold. This seems like a good change that matches the intent of
   mWakeUpComingFromTouch anyway.

Fixes: 284485594
Test: manual: press power button to go to AOD then tap the screen to
wake it back up -> verify falsing threshold increases
Test: manual: on lockscreen, let device time out to go to AOD then tap
the screen to wake it back up -> verify falsing threshold increases

Change-Id: Ie10d61efb9b2ed2639c30f0ee633e74bf19905b7