remove some uses of rafPromise

For simple internal raf, a callback would be better. Once less zone
fired change detection.

ionic/components/action-menu/action-menu.js

@@ -18,7 +18,7 @@ import {Parent} from 'angular2/src/core/annotations_impl/visibility';
 import {Item, Icon} from 'ionic/ionic'
 import {Ionic} from 'ionic/components/app/app'
 import {IonicComponent} from 'ionic/config/component'
-import {raf, rafPromise, ready} from 'ionic/util/dom'
+import {raf, ready} from 'ionic/util/dom'
 import * as util from 'ionic/util'
 
 import {Animation} from 'ionic/animations/animation';

ionic/components/item/item.js

@@ -106,7 +106,7 @@ class Slideable {
   isOpen(open: Boolean) {
     if (arguments.length && open !== this._isOpen) {
       this.isTransitionActive(true)
-      dom.rafPromise().then(() => {
+      dom.raf(() => {
         this.isOpen = isOpen
         this.onSetIsOpen(open)
       })