Use AppSearchModule$Lifecycle class for starting system services in appsearch

ag/16942831 creates a new AppSearchModule class that dispatches system
service lifecycle callbacks to both AppSearchManagerService and
ContactsIndexerManagerService.

Test: refactoring CL. Existing unit tests still pass.

Change-Id: Ia57732d0ad0c5de86a41b08ec4edafa2dca1ce0e