Use array.indexOf native function when available. p=arno, r=ahocevar

git-svn-id: http://svn.openlayers.org/trunk/openlayers@9859 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Util.js

@@ -147,17 +147,21 @@ OpenLayers.Util.clearArray = function(array) {
  * obj - {Object}
  * 
  * Returns:
- * {Integer} The index at, which the object was found in the array.
+ * {Integer} The index at, which the first object was found in the array.
  *           If not found, returns -1.
  */
 OpenLayers.Util.indexOf = function(array, obj) {
-
-    for(var i=0, len=array.length; i<len; i++) {
-        if (array[i] == obj) {
-            return i;
+    // use the build-in function if available.
+    if (typeof array.indexOf == "function") {
+        return array.indexOf(obj);
+    } else {
+        for (var i = 0, len = array.length; i < len; i++) {
+            if (array[i] == obj) {
+                return i;
+            }
         }
+        return -1;   
     }
-    return -1;   
 };