Service/CustomFieldProvider.php
public function getCustomFieldByType($type)
    {
        if (isset($this->servicesByType[$type])) {
            return $this->servicesByType[$type];
        } else {
            throw new \LogicException('the custom field with type '.$type.' '
                . 'is not found');
        }
    }
public function getCustomFieldByType($type)
    {
        if (isset($this->servicesByType[$type])) {
            return $this->servicesByType[$type];
        } else {
            throw new \LogicException('the custom field with type '.$type.' '
                . 'is not found');
        }
    }
Get a custom field stored in the provider. The custom field is identified
by its type.

@param string $type The type of the wanted service
@return CustomFieldInterface