Line 20 of that file is supposed to be non-executable code , same with line 206

From the sound of things, the file may be modified. Suggest heading over to the forum for assistance on this matter.

http://forum.joomla.org

Well my git indicates that no changes were done:
webroot/libraries/joomla/database/driver/mysqli.php

<?php
/**
 * @package     Joomla.Platform
 * @subpackage  Database
 *
 * @copyright   Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE
 */

defined('JPATH_PLATFORM') or die;

/**
 * MySQLi database driver
 *
 * @see    http://php.net/manual/en/book.mysqli.php
 * @since  12.1
 */
class JDatabaseDriverMysqli extends JDatabaseDriver
{
    /**
     * The name of the database driver.
     *
     * @var    string
     * @since  12.1
     */
    public $name = 'mysqli';

    /**
     * The character(s) used to quote SQL statement names such as table names or field names,
     * etc. The child classes should define this as necessary.  If a single character string the
     * same character is used for both sides of the quoted name, else the first character will be
     * used for the opening quote and the second for the closing quote.
     *
     * @var    string
     * @since  12.2
     */
    protected $nameQuote = '`';

    /**
     * The null or zero representation of a timestamp for the database driver.  This should be
     * defined in child classes to hold the appropriate value for the engine.
     *
     * @var    string
     * @since  12.2
     */
    protected $nullDate = '0000-00-00 00:00:00';

    /**
     * @var    string  The minimum supported database version.
     * @since  12.2
     */
    protected static $dbMinimum = '5.0.4';

    /**
     * Constructor.
     *
     * @param   array  $options  List of options used to configure the connection
     *
     * @since   12.1
     */
    public function __construct($options)
    {
        // Get some basic values from the options.
        $options['host']     = (isset($options['host'])) ? $options['host'] : 'localhost';
        $options['user']     = (isset($options['user'])) ? $options['user'] : 'root';
        $options['password'] = (isset($options['password'])) ? $options['password'] : '';
        $options['database'] = (isset($options['database'])) ? $options['database'] : '';
        $options['select']   = (isset($options['select'])) ? (bool) $options['select'] : true;
        $options['port']     = null;
        $options['socket']   = null;

        // Finalize initialisation.
        parent::__construct($options);
    }

    /**
     * Destructor.
     *
     * @since   12.1
     */
    public function __destruct()
    {
        $this->disconnect();
    }

    /**
     * Connects to the database if needed.
     *
     * @return  void  Returns void if the database connected successfully.
     *
     * @since   12.1
     * @throws  RuntimeException
     */
    public function connect()
    {
        if ($this->connection)
        {
            return;
        }

        /*
         * Unlike mysql_connect(), mysqli_connect() takes the port and socket as separate arguments. Therefore, we
         * have to extract them from the host string.
         */
        $port = isset($this->options['port']) ? $this->options['port'] : 3306;
        $regex = '/^(?P<host>((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?))(:(?P<port>.+))?$/';

        if (preg_match($regex, $this->options['host'], $matches))
        {
            // It's an IPv4 address with ot without port
            $this->options['host'] = $matches['host'];

            if (!empty($matches['port']))
            {
                $port = $matches['port'];
            }
        }
        elseif (preg_match('/^(?P<host>\[.*\])(:(?P<port>.+))?$/', $this->options['host'], $matches))
        {
            // We assume square-bracketed IPv6 address with or without port, e.g. [fe80:102::2%eth1]:3306
            $this->options['host'] = $matches['host'];

            if (!empty($matches['port']))
            {
                $port = $matches['port'];
            }
        }
        elseif (preg_match('/^(?P<host>(\w+:\/{2,3})?[a-z0-9\.\-]+)(:(?P<port>[^:]+))?$/i', $this->options['host'], $matches))
        {
            // Named host (e.g domain.com or localhost) with ot without port
            $this->options['host'] = $matches['host'];

            if (!empty($matches['port']))
            {
                $port = $matches['port'];
            }
        }
        elseif (preg_match('/^:(?P<port>[^:]+)$/', $this->options['host'], $matches))
        {
            // Empty host, just port, e.g. ':3306'
            $this->options['host'] = 'localhost';
            $port = $matches['port'];
        }
        // ... else we assume normal (naked) IPv6 address, so host and port stay as they are or default

        // Get the port number or socket name
        if (is_numeric($port))
        {
            $this->options['port'] = (int) $port;
        }
        else
        {
            $this->options['socket'] = $port;
        }

        // Make sure the MySQLi extension for PHP is installed and enabled.
        if (!function_exists('mysqli_connect'))
        {
            throw new RuntimeException('The MySQL adapter mysqli is not available');
        }

        $this->connection = @mysqli_connect(
            $this->options['host'], $this->options['user'], $this->options['password'], null, $this->options['port'], $this->options['socket']
        );

        // Attempt to connect to the server.
        if (!$this->connection)
        {
            throw new RuntimeException('Could not connect to MySQL.');
        }

        // Set sql_mode to non_strict mode
        mysqli_query($this->connection, "SET @@SESSION.sql_mode = '';");

        // If auto-select is enabled select the given database.
        if ($this->options['select'] && !empty($this->options['database']))
        {
            $this->select($this->options['database']);
        }

        // Set charactersets (needed for MySQL 4.1.2+).
        $this->setUtf();

        // Turn MySQL profiling ON in debug mode:
        if ($this->debug && $this->hasProfiling())
        {
            mysqli_query($this->connection, "SET profiling_history_size = 100;");
            mysqli_query($this->connection, "SET profiling = 1;");
        }
    }

    /**
     * Disconnects the database.
     *
     * @return  void
     *
     * @since   12.1
     */
    public function disconnect()
    {
        // Close the connection.
        if ($this->connection instanceof mysqli && $this->connection->stat() !== false)
        {
            foreach ($this->disconnectHandlers as $h)
            {
                call_user_func_array($h, array( &$this));
            }

            mysqli_close($this->connection);
        }

        $this->connection = null;
    }

    /**
     * Method to escape a string for usage in an SQL statement.
     *
     * @param   string   $text   The string to be escaped.
     * @param   boolean  $extra  Optional parameter to provide extra escaping.
     *
     * @return  string  The escaped string.
     *
     * @since   12.1
     */
    public function escape($text, $extra = false)
    {
        $this->connect();

        $result = mysqli_real_escape_string($this->getConnection(), $text);

        if ($extra)
        {
            $result = addcslashes($result, '%_');
        }

        return $result;
    }

    /**
     * Test to see if the MySQL connector is available.
     *
     * @return  boolean  True on success, false otherwise.
     *
     * @since   12.1
     */
    public static function isSupported()
    {
        return (function_exists('mysqli_connect'));
    }

    /**
     * Determines if the connection to the server is active.
     *
     * @return  boolean  True if connected to the database engine.
     *
     * @since   12.1
     */
    public function connected()
    {
        if (is_object($this->connection))
        {
            return mysqli_ping($this->connection);
        }

        return false;
    }

    /**
     * Drops a table from the database.
     *
     * @param   string   $tableName  The name of the database table to drop.
     * @param   boolean  $ifExists   Optionally specify that the table must exist before it is dropped.
     *
     * @return  JDatabaseDriverMysqli  Returns this object to support chaining.
     *
     * @since   12.2
     * @throws  RuntimeException
     */
    public function dropTable($tableName, $ifExists = true)
    {
        $this->connect();

        $query = $this->getQuery(true);

        $this->setQuery('DROP TABLE ' . ($ifExists ? 'IF EXISTS ' : '') . $query->quoteName($tableName));

        $this->execute();

        return $this;
    }

    /**
     * Get the number of affected rows for the previous executed SQL statement.
     *
     * @return  integer  The number of affected rows.
     *
     * @since   12.1
     */
    public function getAffectedRows()
    {
        $this->connect();

        return mysqli_affected_rows($this->connection);
    }

    /**
     * Method to get the database collation.
     *
     * @return  mixed  The collation in use by the database (string) or boolean false if not supported.
     *
     * @since   12.2
     * @throws  RuntimeException
     */
    public function getCollation()
    {
        $this->connect();

        // Attempt to get the database collation by accessing the server system variable.
        $this->setQuery('SHOW VARIABLES LIKE "collation_database"');
        $result = $this->loadObject();

        if (property_exists($result, 'Value'))
        {
            return $result->Value;
        }
        else
        {
            return false;
        }
    }

    /**
     * Get the number of returned rows for the previous executed SQL statement.
     *
     * @param   resource  $cursor  An optional database cursor resource to extract the row count from.
     *
     * @return  integer   The number of returned rows.
     *
     * @since   12.1
     */
    public function getNumRows($cursor = null)
    {
        return mysqli_num_rows($cursor ? $cursor : $this->cursor);
    }

    /**
     * Shows the table CREATE statement that creates the given tables.
     *
     * @param   mixed  $tables  A table name or a list of table names.
     *
     * @return  array  A list of the create SQL for the tables.
     *
     * @since   12.1
     * @throws  RuntimeException
     */
    public function getTableCreate($tables)
    {
        $this->connect();

        $result = array();

        // Sanitize input to an array and iterate over the list.
        settype($tables, 'array');

        foreach ($tables as $table)
        {
            // Set the query to get the table CREATE statement.
            $this->setQuery('SHOW CREATE table ' . $this->quoteName($this->escape($table)));
            $row = $this->loadRow();

            // Populate the result array based on the create statements.
            $result[$table] = $row[1];
        }

        return $result;
    }

    /**
     * Retrieves field information about a given table.
     *
     * @param   string   $table     The name of the database table.
     * @param   boolean  $typeOnly  True to only return field types.
     *
     * @return  array  An array of fields for the database table.
     *
     * @since   12.2
     * @throws  RuntimeException
     */
    public function getTableColumns($table, $typeOnly = true)
    {
        $this->connect();

        $result = array();

        // Set the query to get the table fields statement.
        $this->setQuery('SHOW FULL COLUMNS FROM ' . $this->quoteName($this->escape($table)));
        $fields = $this->loadObjectList();

        // If we only want the type as the value add just that to the list.
        if ($typeOnly)
        {
            foreach ($fields as $field)
            {
                $result[$field->Field] = preg_replace("/[(0-9)]/", '', $field->Type);
            }
        }
        // If we want the whole field data object add that to the list.
        else
        {
            foreach ($fields as $field)
            {
                $result[$field->Field] = $field;
            }
        }

        return $result;
    }

    /**
     * Get the details list of keys for a table.
     *
     * @param   string  $table  The name of the table.
     *
     * @return  array  An array of the column specification for the table.
     *
     * @since   12.2
     * @throws  RuntimeException
     */
    public function getTableKeys($table)
    {
        $this->connect();

        // Get the details columns information.
        $this->setQuery('SHOW KEYS FROM ' . $this->quoteName($table));
        $keys = $this->loadObjectList();

        return $keys;
    }

    /**
     * Method to get an array of all tables in the database.
     *
     * @return  array  An array of all the tables in the database.
     *
     * @since   12.2
     * @throws  RuntimeException
     */
    public function getTableList()
    {
        $this->connect();

        // Set the query to get the tables statement.
        $this->setQuery('SHOW TABLES');
        $tables = $this->loadColumn();

        return $tables;
    }

    /**
     * Get the version of the database connector.
     *
     * @return  string  The database connector version.
     *
     * @since   12.1
     */
    public function getVersion()
    {
        $this->connect();

        return mysqli_get_server_info($this->connection);
    }

    /**
     * Method to get the auto-incremented value from the last INSERT statement.
     *
     * @return  mixed  The value of the auto-increment field from the last inserted row.
     *                 If the value is greater than maximal int value, it will return a string.
     *
     * @since   12.1
     */
    public function insertid()
    {
        $this->connect();

        return mysqli_insert_id($this->connection);
    }

    /**
     * Locks a table in the database.
     *
     * @param   string  $table  The name of the table to unlock.
     *
     * @return  JDatabaseDriverMysqli  Returns this object to support chaining.
     *
     * @since   12.2
     * @throws  RuntimeException
     */
    public function lockTable($table)
    {
        $this->setQuery('LOCK TABLES ' . $this->quoteName($table) . ' WRITE')->execute();

        return $this;
    }

    /**
     * Execute the SQL statement.
     *
     * @return  mixed  A database cursor resource on success, boolean false on failure.
     *
     * @since   12.1
     * @throws  RuntimeException
     */
    public function execute()
    {
        $this->connect();

        if (!is_object($this->connection))
        {
            JLog::add(JText::sprintf('JLIB_DATABASE_QUERY_FAILED', $this->errorNum, $this->errorMsg), JLog::ERROR, 'database');
            throw new RuntimeException($this->errorMsg, $this->errorNum);
        }

        // Take a local copy so that we don't modify the original query and cause issues later
        $query = $this->replacePrefix((string) $this->sql);

        if (!($this->sql instanceof JDatabaseQuery) && ($this->limit > 0 || $this->offset > 0))
        {
            $query .= ' LIMIT ' . $this->offset . ', ' . $this->limit;
        }

        // Increment the query counter.
        $this->count++;

        // Reset the error values.
        $this->errorNum = 0;
        $this->errorMsg = '';
        $memoryBefore   = null;

        // If debugging is enabled then let's log the query.
        if ($this->debug)
        {
            // Add the query to the object queue.
            $this->log[] = $query;

            JLog::add($query, JLog::DEBUG, 'databasequery');

            $this->timings[] = microtime(true);

            if (is_object($this->cursor))
            {
                // Avoid warning if result already freed by third-party library
                @$this->freeResult();
            }

            $memoryBefore = memory_get_usage();
        }

        // Execute the query. Error suppression is used here to prevent warnings/notices that the connection has been lost.
        $this->cursor = @mysqli_query($this->connection, $query);

        if ($this->debug)
        {
            $this->timings[] = microtime(true);

            if (defined('DEBUG_BACKTRACE_IGNORE_ARGS'))
            {
                $this->callStacks[] = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
            }
            else
            {
                $this->callStacks[] = debug_backtrace();
            }

            $this->callStacks[count($this->callStacks) - 1][0]['memory'] = array(
                $memoryBefore,
                memory_get_usage(),
                is_object($this->cursor) ? $this->getNumRows() : null
            );
        }

        // If an error occurred handle it.
        if (!$this->cursor)
        {
            $this->errorNum = (int) mysqli_errno($this->connection);
            $this->errorMsg = (string) mysqli_error($this->connection) . ' SQL=' . $query;

            // Check if the server was disconnected.
            if (!$this->connected())
            {
                try
                {
                    // Attempt to reconnect.
                    $this->connection = null;
                    $this->connect();
                }
                // If connect fails, ignore that exception and throw the normal exception.
                catch (RuntimeException $e)
                {
                    JLog::add(JText::sprintf('JLIB_DATABASE_QUERY_FAILED', $this->errorNum, $this->errorMsg), JLog::ERROR, 'database-error');
                    throw new RuntimeException($this->errorMsg, $this->errorNum);
                }

                // Since we were able to reconnect, run the query again.
                return $this->execute();
            }
            // The server was not disconnected.
            else
            {
                JLog::add(JText::sprintf('JLIB_DATABASE_QUERY_FAILED', $this->errorNum, $this->errorMsg), JLog::ERROR, 'database-error');
                throw new RuntimeException($this->errorMsg, $this->errorNum);
            }
        }

        return $this->cursor;
    }

    /**
     * Renames a table in the database.
     *
     * @param   string  $oldTable  The name of the table to be renamed
     * @param   string  $newTable  The new name for the table.
     * @param   string  $backup    Not used by MySQL.
     * @param   string  $prefix    Not used by MySQL.
     *
     * @return  JDatabaseDriverMysqli  Returns this object to support chaining.
     *
     * @since   12.2
     * @throws  RuntimeException
     */
    public function renameTable($oldTable, $newTable, $backup = null, $prefix = null)
    {
        $this->setQuery('RENAME TABLE ' . $oldTable . ' TO ' . $newTable)->execute();

        return $this;
    }

    /**
     * Select a database for use.
     *
     * @param   string  $database  The name of the database to select for use.
     *
     * @return  boolean  True if the database was successfully selected.
     *
     * @since   12.1
     * @throws  RuntimeException
     */
    public function select($database)
    {
        $this->connect();

        if (!$database)
        {
            return false;
        }

        if (!mysqli_select_db($this->connection, $database))
        {
            throw new RuntimeException('Could not connect to database.');
        }

        return true;
    }

    /**
     * Set the connection to use UTF-8 character encoding.
     *
     * @return  boolean  True on success.
     *
     * @since   12.1
     */
    public function setUtf()
    {
        $this->connect();

        return $this->connection->set_charset('utf8');
    }

    /**
     * Method to commit a transaction.
     *
     * @param   boolean  $toSavepoint  If true, commit to the last savepoint.
     *
     * @return  void
     *
     * @since   12.2
     * @throws  RuntimeException
     */
    public function transactionCommit($toSavepoint = false)
    {
        $this->connect();

        if (!$toSavepoint || $this->transactionDepth <= 1)
        {
            if ($this->setQuery('COMMIT')->execute())
            {
                $this->transactionDepth = 0;
            }

            return;
        }

        $this->transactionDepth--;
    }

    /**
     * Method to roll back a transaction.
     *
     * @param   boolean  $toSavepoint  If true, rollback to the last savepoint.
     *
     * @return  void
     *
     * @since   12.2
     * @throws  RuntimeException
     */
    public function transactionRollback($toSavepoint = false)
    {
        $this->connect();

        if (!$toSavepoint || $this->transactionDepth <= 1)
        {
            if ($this->setQuery('ROLLBACK')->execute())
            {
                $this->transactionDepth = 0;
            }

            return;
        }

        $savepoint = 'SP_' . ($this->transactionDepth - 1);
        $this->setQuery('ROLLBACK TO SAVEPOINT ' . $this->quoteName($savepoint));

        if ($this->execute())
        {
            $this->transactionDepth--;
        }
    }

    /**
     * Method to initialize a transaction.
     *
     * @param   boolean  $asSavepoint  If true and a transaction is already active, a savepoint will be created.
     *
     * @return  void
     *
     * @since   12.2
     * @throws  RuntimeException
     */
    public function transactionStart($asSavepoint = false)
    {
        $this->connect();

        if (!$asSavepoint || !$this->transactionDepth)
        {
            if ($this->setQuery('START TRANSACTION')->execute())
            {
                $this->transactionDepth = 1;
            }

            return;
        }

        $savepoint = 'SP_' . $this->transactionDepth;
        $this->setQuery('SAVEPOINT ' . $this->quoteName($savepoint));

        if ($this->execute())
        {
            $this->transactionDepth++;
        }
    }

    /**
     * Method to fetch a row from the result set cursor as an array.
     *
     * @param   mixed  $cursor  The optional result set cursor from which to fetch the row.
     *
     * @return  mixed  Either the next row from the result set or false if there are no more rows.
     *
     * @since   12.1
     */
    protected function fetchArray($cursor = null)
    {
        return mysqli_fetch_row($cursor ? $cursor : $this->cursor);
    }

    /**
     * Method to fetch a row from the result set cursor as an associative array.
     *
     * @param   mixed  $cursor  The optional result set cursor from which to fetch the row.
     *
     * @return  mixed  Either the next row from the result set or false if there are no more rows.
     *
     * @since   12.1
     */
    protected function fetchAssoc($cursor = null)
    {
        return mysqli_fetch_assoc($cursor ? $cursor : $this->cursor);
    }

    /**
     * Method to fetch a row from the result set cursor as an object.
     *
     * @param   mixed   $cursor  The optional result set cursor from which to fetch the row.
     * @param   string  $class   The class name to use for the returned row object.
     *
     * @return  mixed   Either the next row from the result set or false if there are no more rows.
     *
     * @since   12.1
     */
    protected function fetchObject($cursor = null, $class = 'stdClass')
    {
        return mysqli_fetch_object($cursor ? $cursor : $this->cursor, $class);
    }

    /**
     * Method to free up the memory used for the result set.
     *
     * @param   mixed  $cursor  The optional result set cursor from which to fetch the row.
     *
     * @return  void
     *
     * @since   12.1
     */
    protected function freeResult($cursor = null)
    {
        mysqli_free_result($cursor ? $cursor : $this->cursor);

        if ((! $cursor) || ($cursor === $this->cursor))
        {
            $this->cursor = null;
        }
    }

    /**
     * Unlocks tables in the database.
     *
     * @return  JDatabaseDriverMysqli  Returns this object to support chaining.
     *
     * @since   12.1
     * @throws  RuntimeException
     */
    public function unlockTables()
    {
        $this->setQuery('UNLOCK TABLES')->execute();

        return $this;
    }

    /**
     * Internal function to check if profiling is available
     *
     * @return  boolean
     *
     * @since 3.1.3
     */
    private function hasProfiling()
    {
        try
        {
            $res = mysqli_query($this->connection, "SHOW VARIABLES LIKE 'have_profiling'");
            $row = mysqli_fetch_assoc($res);

            return isset($row);
        }
        catch (Exception $e)
        {
            return false;
        }
    }
}