[bugfix] When writing the end of an XML element, make sure that the correct prefix is used after coalescing namespace prefixes

Closes #61

Author: adamretter

exist-core/src/main/java/org/exist/util/serializer/SAXSerializer.java

@@ -400,7 +400,7 @@ public void endElement(final QName qname) throws SAXException {
             if (enforceXHTML && elemPrefix.isEmpty() && namespaceURI.isEmpty()) {
                 namespaceURI = Namespaces.XHTML_NS;
             }
-            receiver.endElement(new QName(qname.getLocalPart(), namespaceURI, qname.getPrefix()));
+            receiver.endElement(new QName(qname.getLocalPart(), namespaceURI, elemPrefix));
 
             receiver.setDefaultNamespace(nsSupport.getURI(XMLConstants.DEFAULT_NS_PREFIX));
         } catch (final TransformerException e) {

exist-core/src/test/java/org/exist/util/serializer/SAXSerializerTest.java

@@ -96,7 +96,7 @@ public void coalesceNamespacePrefixesFromQName() throws SAXException {
             saxSerializer.endElement(new QName("change", "http://exist-db.org/xquery/repo", "repo"));
 
             saxSerializer.startElement(new QName("change", "http://exist-db.org/xquery/repo", "repo"), null);
-            saxSerializer.characters("change-text-1");
+            saxSerializer.characters("change-text-2");
             saxSerializer.endElement(new QName("change", "http://exist-db.org/xquery/repo", "repo"));
 
             saxSerializer.endElement(new QName("changelog", "http://exist-db.org/xquery/repo", null));