The __construct function in SequenceMatcher produces Deprecated: Optional parameter $junkCallback declared before required parameter $options is implicitly treated as a required parameter [i.e. $junkCallback has a default but $options does not]
public function __construct($a, $b, $junkCallback=null, $options)
Quick fix might be :
public function __construct($a, $b, $junkCallback=null, $options=null)