perf($q): only bind Deferred methods when returned publicly from $q.defer

Author: jbedard

src/ng/q.js

@@ -267,7 +267,12 @@ function qFactory(nextTick, exceptionHandler) {
    * @returns {Deferred} Returns a new instance of deferred.
    */
   var defer = function() {
-    return new Deferred();
+    var d = new Deferred();
+    //Necessary to support unbound execution :/
+    d.resolve = simpleBind(d, d.resolve);
+    d.reject = simpleBind(d, d.reject);
+    d.notify = simpleBind(d, d.notify);
+    return d;
   };
 
   function Promise() {
@@ -340,10 +345,6 @@ function qFactory(nextTick, exceptionHandler) {
 
   function Deferred() {
     this.promise = new Promise();
-    //Necessary to support unbound execution :/
-    this.resolve = simpleBind(this, this.resolve);
-    this.reject = simpleBind(this, this.reject);
-    this.notify = simpleBind(this, this.notify);
   }
 
   extend(Deferred.prototype, {
@@ -368,7 +369,7 @@ function qFactory(nextTick, exceptionHandler) {
         if ((isObject(val) || isFunction(val))) then = val && val.then;
         if (isFunction(then)) {
           this.promise.$$state.status = -1;
-          then.call(val, fns[0], fns[1], this.notify);
+          then.call(val, fns[0], fns[1], simpleBind(this, this.notify));
         } else {
           this.promise.$$state.value = val;
           this.promise.$$state.status = 1;