Currently, Java clients are manually creating the StatsEvent objects
which can lead to errors. Now that there is support for pulled atoms for
stats-log-api-gen for Java clients, use the appropriate buildStatsEvent
method that was auto generated by stats-log-api-gen.
Bug: 160368804
Test: Ran `m` and completed successfully
Test: Ran `atest statsd_test` and all CTS tests passed
Test: Ran `atest UidAtomTests` and all CTS tests passed except for the CTS tests related to a SIM card because the device does not have a SIM card
Change-Id: Id229ba5ca94203135a8a5e2607de9844e0432ce1