NetworkStatsHistory internally assumes that bucketStart is
sorted at all times. However, in the fields, we've found there
are some buckets of NetworkStatsHistory do not preserve the
order of timestamp, which is caught by the IAE when addEntry
is called.
In order to provide backward compatibility, return sorted items
instead of throwing IAE when adding entry into
NetworkStatsHistory instance.
Test: atest android.net.netstats.NetworkStatsHistoryTest#testBuilder
Bug: 233825704
Change-Id: If3187384bd1e90770ca5873b8ec73e852fff543d
Merged-In: If3187384bd1e90770ca5873b8ec73e852fff543d
(pure cherry-picked from ag/18581718)
bfdd4407eb