Remove kTruncatingTimestampAtomBlackList

Use shouldTruncateTimestamp flag in LogEvent instead of the blacklist
to determine whether timestamp should be truncated.

Bug: 150414373
Test: bit statsd_test:*
Change-Id: I4e21ae4909484dd898b9fcd3ce7a018f5e9d982f
diff --git a/cmds/statsd/src/metrics/GaugeMetricProducer.cpp b/cmds/statsd/src/metrics/GaugeMetricProducer.cpp
index 42bbd8e..c4bd054 100644
--- a/cmds/statsd/src/metrics/GaugeMetricProducer.cpp
+++ b/cmds/statsd/src/metrics/GaugeMetricProducer.cpp
@@ -270,11 +270,9 @@
                     protoOutput->end(atomsToken);
                 }
                 for (const auto& atom : bucket.mGaugeAtoms) {
-                    const int64_t elapsedTimestampNs =
-                            truncateTimestampIfNecessary(mAtomId, atom.mElapsedTimestamps);
-                    protoOutput->write(
-                        FIELD_TYPE_INT64 | FIELD_COUNT_REPEATED | FIELD_ID_ELAPSED_ATOM_TIMESTAMP,
-                        (long long)elapsedTimestampNs);
+                    protoOutput->write(FIELD_TYPE_INT64 | FIELD_COUNT_REPEATED |
+                                               FIELD_ID_ELAPSED_ATOM_TIMESTAMP,
+                                       (long long)atom.mElapsedTimestampNs);
                 }
             }
             protoOutput->end(bucketInfoToken);
@@ -477,7 +475,9 @@
     if ((*mCurrentSlicedBucket)[eventKey].size() >= mGaugeAtomsPerDimensionLimit) {
         return;
     }
-    GaugeAtom gaugeAtom(getGaugeFields(event), eventTimeNs);
+
+    const int64_t truncatedElapsedTimestampNs = truncateTimestampIfNecessary(event);
+    GaugeAtom gaugeAtom(getGaugeFields(event), truncatedElapsedTimestampNs);
     (*mCurrentSlicedBucket)[eventKey].push_back(gaugeAtom);
     // Anomaly detection on gauge metric only works when there is one numeric
     // field specified.