comments and fix test

Author: fandreuz

sdk/metrics/src/main/java/io/opentelemetry/sdk/metrics/internal/state/AsynchronousMetricStorage.java

@@ -225,7 +225,8 @@ private Collection<T> collectWithDeltaAggregationTemporality() {
                   AsynchronousMetricStorage.this.startEpochNanos,
                   AsynchronousMetricStorage.this.epochNanos,
                   attributes,
-                  /* reset= */ true);
+                  // No need to reset, aggregatorHandles is going to be cleared anyways
+                  /* reset= */ false);
           currentPoints.put(attributes, value);
         });
 
@@ -257,6 +258,8 @@ private Collection<T> collectWithDeltaAggregationTemporality() {
       Map<Attributes, T> tmp = lastPoints;
       lastPoints = reusablePointsMap;
       reusablePointsMap = tmp;
+    } else {
+      lastPoints = currentPoints;
     }
 
     return deltaPoints;
@@ -271,6 +274,7 @@ private Collection<T> collectWithCumulativeAggregationTemporality() {
                   AsynchronousMetricStorage.this.startEpochNanos,
                   AsynchronousMetricStorage.this.epochNanos,
                   attributes,
+                  // No need to reset, aggregatorHandles is going to be cleared anyways
                   /* reset= */ false);
           currentPoints.add(value);
         });