CM-SDK: add PREDISMISSED_STATE constant required by CM13 DeskClock

See http://review.cyanogenmod.org/#/c/125484 which brings the
changes to allow third party components to set and modify alarms,
and which actually makes use of the ClockContract in the SDK. This
flushes out the fact that the ClockContract in CM13 added a new
state.

Change-Id: If6d57727298c0a749055337809b9a66e91078a01