perf(extend): remove use of forEach to remove calls/closures/passing arguments

Author: jbedard

src/Angular.js

@@ -337,13 +337,16 @@ function setHashKey(obj, h) {
  */
 function extend(dst) {
   var h = dst.$$hashKey;
-  forEach(arguments, function(obj) {
+  for (var i = 1, ii = arguments.length; i < ii; i++) {
+    var obj = arguments[i];
     if (obj !== dst) {
-      forEach(obj, function(value, key) {
-        dst[key] = value;
-      });
+      for (var key in obj) {
+        if (obj.hasOwnProperty(key)) {
+          dst[key] = obj[key];
+        }
+      }
     }
-  });
+  }
 
   setHashKey(dst,h);
   return dst;