@Override
  public boolean hasEvictionThreshold() {
    return hasEvictionThreshold;
  }
Called at the beginning of updateStateAndSendEvent.

@param bytesUsed the number of bytes of off-heap memory currently used
@param willSendEvent true if an event will be sent to the OffHeapMemoryUsageListener.
geode-core/src/main/java/org/apache/geode/internal/cache/control/OffHeapMemoryMonitor.java