Tribe__Tickets__Commerce__PayPal__Cart__Unmanaged::remove_item( $item_id, $quantity = null )
{@inheritdoc}
Source
File: src/Tribe/Commerce/PayPal/Cart/Unmanaged.php
public function remove_item( $item_id, $quantity ) {
$this->add_item( $item_id, - abs( (int) $quantity ) );
}