Anomaly detection statsdstats

Adds statsdstats for tracking the number of anomaly alarms registered.

Test: adb shell data/nativetest64/statsd_test/statsd_test
Bug: 67978682
Change-Id: I4aa0539a13c60ccb3b7fd2a4f41c4ad867f3a4ea
diff --git a/cmds/statsd/src/StatsService.h b/cmds/statsd/src/StatsService.h
index bdae1ef..e434f65 100644
--- a/cmds/statsd/src/StatsService.h
+++ b/cmds/statsd/src/StatsService.h
@@ -46,6 +46,10 @@
     StatsService(const sp<Looper>& handlerLooper);
     virtual ~StatsService();
 
+    /** The anomaly alarm registered with AlarmManager won't be updated by less than this. */
+    // TODO: Consider making this configurable. And choose a good number.
+    const uint32_t MIN_DIFF_TO_UPDATE_REGISTERED_ALARM_SECS = 5;
+
     virtual status_t onTransact(uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags);
     virtual status_t dump(int fd, const Vector<String16>& args);
     virtual status_t command(FILE* in, FILE* out, FILE* err, Vector<String8>& args);