Add sharding to BinderCallsStats collection and make it configurable. The

hash code of the callsession will be used to select which apis will be
collected for based on the configured modulo. This is needed to reduce
the amount of data collected from public devices.

Test: unit tests
Bug: 180584913
Change-Id: I66ea9ad9a7f4b66b135358ac899ed425c731760a