Extract battery saver and uid checks to VibrationSettings

Extract PowerManagerInternal.LowPowerModeListener and IUidObserver code
to VibrationSettings, exposing two new "shouldVibrateFor***" methods
called by both Vibrator and VibratorManager services.

Bug: 167946816
Bug: 131311651
Test: atest FrameworksServiceTests:VibratorServiceTest
      atest FrameworksServiceTests:VibrationSettingsTest
Change-Id: I20fa6df781fa394afcd61c2b79b826e430b01600