Major Description
When using the debugger and displaying the infoset (e.g. info infoset), if the current element is a prefixed length element Daffodil will abort with an exception about "No parent element for element (prefixLength)". This is because the debugger tries to find the root element:
infoset = infoset.toRootDoc.getRootElement().asInstanceOf[DIElement]
But that fails when the element is a prefixed length element. Need special logic somewhere to handle these detached elements.