Fix fail to search by input "4G Calling"

Fixed step:
1.Update resource xml file in SearchIndexProvider.
2.Add keywords for preference title array.
3.Initizlize data member.
When getAvailabilityStatus called by updateNonIndexableKeys,
the data member should be initialized,
otherwise it always returns CONDITIONALLY_UNAVAILABLE

Fixes: 137155154
Test: manual
Change-Id: Id06d78bffdeba247741dcfe81e9ed7e179141397