private HandshakeStatus runDelegatedTasks() {
    for (; ; ) {
      Runnable task = delegatedTask();
      if (task == null) {
        break;
      }
      task.run();
    }
    return sslEngine.getHandshakeStatus();
  }
Executes the SSLEngine tasks needed.
@return HandshakeStatus
ambry-network/src/main/java/com/github/ambry/network/SSLTransmission.java