spec on USBDevice.open() doesn't mention SecurityError

[dlech]

The spec at https://wicg.github.io/webusb/#dom-usbdevice-open

says that open() can raise a DOMException with "NotFoundError" or "NetworkError".

However a "SecurityError" has been observed on Linux, e.g. if udev rules are not provided.

This is useful to be able to handle the error separately from any other error that might occur. So it should be part of the formal spec.

[reillyeon]

The implementation is a little broken in that any failure to open the device is treated as a permission error but I agree that differentiating between errors the user can fix and hardware issues is helpful.