Trackball/LED fixes:

- Disable "blend mode" for sholes
- Make LightsService use a different method for turning off LED/trackball-
  on some devices (ok, droid), the previous method was causing the LED to stay on
  continuously.
- Fix bug that was causing the custom offTime for notifications to be ignored.

Change-Id: I89123555dd813e1ff67f70ff2874761c229b9522