public boolean updateStateAndSendEvent() {
    return updateStateAndSendEvent(getBytesUsed());
  }
Compare the number of bytes used (fetched from the JVM) to the thresholds. If necessary, change
the state and send an event for the state change.

@return true if an event was sent
geode-core/src/main/java/org/apache/geode/internal/cache/control/OffHeapMemoryMonitor.java