Adding an extra check for IE, where request.responseXML is true on occasion even if the documentElement doesn't exist. r=crschmidt (closes #1428)

git-svn-id: http://svn.openlayers.org/trunk/openlayers@6573 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Tile/WFS.js

@@ -127,9 +127,8 @@ OpenLayers.Tile.WFS = OpenLayers.Class(OpenLayers.Tile, {
     requestSuccess:function(request) {
         if (this.features) {
             var doc = request.responseXML;
-            
-            if (!doc) {
-                doc = OpenLayers.parseXMLString(request.responseText);
+            if (!doc || !doc.documentElement) {
+                doc = OpenLayers.Format.XML.prototype.read(request.responseText);
             }
             if (this.layer.vectorMode) {
                 this.layer.addFeatures(this.layer.formatObject.read(doc));