reverting r10905, which included more changes than it should have

git-svn-id: http://svn.openlayers.org/trunk/openlayers@10906 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Util.js

@@ -1633,12 +1633,10 @@ OpenLayers.Util.removeTail = function(url) {
 
 /**
  * Constant: IS_GECKO
- * {Boolean} True if the navigator.userAgent property reports the browser to
- * use the Gecko engine
+ * {Boolean} True if the userAgent reports the browser to use the Gecko engine
  */
 OpenLayers.IS_GECKO = (function() {
-    var ua = navigator.userAgent.toLowerCase();
-    return ua.indexOf("gecko") != -1 && ua.indexOf("webkit") == -1;
+    return navigator.userAgent.toLowerCase().indexOf("gecko") != -1;
 })();
 
 /**