[Windows] AddConnectionStatusChanged callback

[dbogoslovtsev]

Hi! I noticed the recent activity in the dev branch (#319). Thanks for the fixes!
I’d like to take it a step further and get AddConnectionStatusChanged/RemoveConnectionStatusChanged working on the Windows target.
I tried implementing something like this, but the callback doesn’t seem to work:

	var handler *foundation.TypedEventHandler
	handler = foundation.NewTypedEventHandler(
		ole.NewGUID(winrt.ParameterizedInstanceGUID(
			foundation.GUIDTypedEventHandler,
			bluetooth.SignatureBluetoothLEDevice,
			bluetooth.SignatureBluetoothConnectionStatus,
		)),
		func(instance *foundation.TypedEventHandler, sender, args unsafe.Pointer) {
			println("TypedEventHandlerCallback")
			println(instance)
			println(sender)
			println(args)

			if a.connectHandler != nil {
				a.connectHandler(device, false)
			}
		})
	bleDevice.AddConnectionStatusChanged(handler)

Is there any chance you might implement this later? Or do you have any suggestions on how to make it work properly?