Description:
------------
When I try to connect to a Mysql database using SSL and mysqli, it says that the method ssl_set don't exists. I used function get_class_methods(mysqli) and is not listed. I checked mysql support, mysqli support and openssl support with phpinfo and they are all supported.

Here is the list returned from get_class_methods:
autocommit
change_user
character_set_name
client_encoding
close
commit
connect
dump_debug_info
debug
get_charset
get_client_info
get_connection_stats
get_server_info
get_warnings
init
kill
multi_query
mysqli
more_results
next_result
options
ping
prepare
query
real_connect
real_escape_string
poll
reap_async_query
escape_string
real_query
rollback
select_db
set_charset
set_opt
stat
stmt_init
store_result
thread_safe
use_result
refresh

Reproduce code:
---------------
$mysqli= mysqli_init();

if (!$mysqli) {
	die('mysqli_init failed');
}

$mysqli->ssl_set('path/to/key.pem','path/to/cert.pem','path/to/cacert.pem',null,null);

$mysqli_real_connect('1.2.3.4','ssluser','sslpassword','db',port,MYSQLI_CLIENT_SSL);

//queries

$mysqli->close();

Expected result:
----------------
A secure connection to mysql

Actual result:
--------------
Fatal error: Call to undefined method mysqli::ssl_set() in ...