Doctrine MasterSlaveConnection beginTransaction connects to master but does NOT call parent method

NewMasterSlaveConnection.php

<?php

<?php

class NewMasterSlaveConnection
{
    public function beginTransaction()
    {
        $this->connect('master');

        // *** Copied from the parent method except don't connect again ***
        ++$this->_transactionNestingLevel;

        $logger = $this->_config->getSQLLogger();

        if ($this->_transactionNestingLevel == 1) {
            if ($logger) {
                $logger->startQuery('"START TRANSACTION"');
            }
            $this->_conn->beginTransaction();
            if ($logger) {
                $logger->stopQuery();
            }
        } else if ($this->_nestTransactionsWithSavepoints) {
            if ($logger) {
                $logger->startQuery('"SAVEPOINT"');
            }
            $this->createSavepoint($this->_getNestedTransactionSavePointName());
            if ($logger) {
                $logger->stopQuery();
            }
        }
    }
}