Doze: Follow the notification light.

 - Send the notification light info up to SystemUI from NoMan.
 - Doze mode will now periodically pulse the display (once)
   if the notification light is active.
 - Change "tease" terminology to "pulse", which is the singular.
   Maintain the multi-pulse on buzz-beep-blink for now as extra
   emphasis.
 - Scrim controller now always takes number of pulses as an arg,
   to support a single pulse (used for notification light, and
   eventually pickup once available).
 - Dial down the display brightness when pulsing.

Bug:15863249
Change-Id: Ifb208a27e82b66cff1d0c04e5b7f758098ea29cf