make Format.ArcXML tests pass in Safari, invalid XML documents are dealt with differently in Safari, r=elemoine (closes #2626)

git-svn-id: http://svn.openlayers.org/trunk/openlayers@10302 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Format/ArcXML.js

@@ -221,7 +221,9 @@ OpenLayers.Format.ArcXML = OpenLayers.Class(OpenLayers.Format.XML, {
             }
         }
           
-        if (!arcNode) {
+        // in Safari, arcNode will be there but will have a child named 
+        // parsererror
+        if (!arcNode || arcNode.firstChild.nodeName === 'parsererror') {
             var error, source;
             try {
                 error = data.firstChild.nodeValue;