Implementation of SEARCH_MODE for Alarms.

Implemented SEARCH_MODE_TIME, SEARCH_MODE_NEXT, SEARCH_MODE_ALL.
This CL doesn't implement the case when search mode == null, will be in the next CL.
SEARCH_MODE_* is used by Alarms in methods CANCEL_ALARM and DELETE_ALARM.
In StopwatchFragment and StopwatchService changed apply() to commit() to get rid of asynchronous calls.
 Test cases (added in a separate CL) used to fail with apply() because the state of SharedPreferences
  wasn't as expected.

Change-Id: I0b8dad39088ef8fe7a5bfea816f31cebac4fb3e3