Media that contains null in id can't be added into playlist

[kachaj7]

alpha/apps/kaltura/lib/myPlaylistUtils.class.php

Method: validatePlaylist

contains

// TODO - hack for removing 'null' from the entry id due to a bug on the client's side
$trimmed = preg_replace ( "/null/" , "" , trim ( $entry_id ) );
if ($trimmed)
{
	$fixed_playlist[] = $trimmed;
	self::validatePlaylistInnerEntry($trimmed);
}

validatePlaylistInnerEntry - method throws exception, because id not found.