[bugfix] fn:parse-xml-fragment#1 should return a document-node() when…

… there is an XML document that has a XML declaration

exist-core/src/main/java/org/exist/xquery/functions/fn/ParsingFunctions.java

@@ -105,7 +105,7 @@ private Sequence parse(final String xmlContent, final Sequence[] args) throws XP
 
     private ValidationReport validate(final String xmlContent, final SAXAdapter saxAdapter) throws XPathException {
         final String xml;
-	    if (isCalledAs("parse-xml-fragment")) {
+	    if (isCalledAs("parse-xml-fragment") && !xmlContent.toLowerCase().startsWith("<?xml ")) {
             xml = "<" + FRAGMENT_WRAPPER_NAME + ">" + xmlContent + "</" + FRAGMENT_WRAPPER_NAME + ">";
         } else {
 	        xml = xmlContent;