code: func (c *connectionFlowController) IncrementHighestReceived(increment protocol.ByteCount) error {
  	c.mutex.Lock()
  	defer c.mutex.Unlock()
  
  	c.highestReceived += increment
  	if c.checkFlowControlViolation() {
  		return qerr.Error(qerr.FlowControlError, fmt.Sprintf("Received %d bytes for the connection, allowed %d bytes", c.highestReceived, c.receiveWindow))
  	}
  	return nil
  }
docs: // IncrementHighestReceived adds an increment to the highestReceived value