E-notice fix

This e-Notice

Undefined variable: contactID Notice Register.php 1024 CRM_Event_Form_Registration_Register->postProcess()

It seemss to me that in this line $contactID will never be set as I couldn't find it anywhere else in the function (and that processRegistration will ignore it if set) but wanted another pair of eyes.

self::processRegistration( $this->_params, $contactID );

Change to

self::processRegistration( $this->_params);