add shutdown animation

- Run shutdown animation during shutdown if surfaceflinger is
  available / running.
- services necessary for animation should be added to animation
  class.
- Keep debugging tools while non-critical services are terminated:
  logd, adbd, tombstoned

bug: 36526187
Test: many reboots

(cherry picked from commit 7830d59500eb0cb24333dc357ac5bed38270e181)

Change-Id: I83011e3f843e6b64c56c453a996db738f497877a
2 files changed