Ignore errors when accessing selection* properties in WebKit-based browsers

[ipromax]

If we create an input element with type checkbox (or radio, file, etc) will raise an exception TypeError: Type error if you try to access selectionStart, selectionEnd, selectionDirection. This problem can be reproduced on play.vugu.org  (Safari 15.2)

[bradleypeabody]

Thanks for tracking this down!