protected void processAlerts(HeartBeat heartbeat) {
    if (heartbeat != null) {
      processAlerts(heartbeat.getHostname(), heartbeat.getAlerts());
    }
  }
Extracts all of the {@link Alert}s from the heartbeat and fires
{@link AlertEvent}s for each one. If there is a problem looking up the
cluster, then alerts will not be processed.

@param heartbeat the heartbeat to process.
ambari-server/src/main/java/org/apache/ambari/server/agent/HeartbeatProcessor.java