Statsd AnomalyDetection stopAlarm also checks old

Every time stopAlarm() is called, it should also,
right then, check to see if the alarm should actually
have already fired (but didn't due to AlarmManager lag).
Right now, the client needs to do this check separately,
but they always go together. Indeed, MaxDurationTracker
forgot to do the check, which is a bug. It would make
much more sense if the stopAlarm takes care of it for
them, to prevent such mistakes.

Bug: 75273733
Test: make statsd_test && adb sync data && adb shell data/nativetest64/statsd_test/statsd_test
Test: cts-tradefed run cts-dev -m CtsStatsdHostTestCases -t android.cts.statsd.alert
Change-Id: I689df13690df822090ac34b1171e948be1ad0d9f