feat($uiViewScroll): change function to return promise

return the promise from the timeout for additional processing

Closes #1702

Author: mikef438

src/viewScroll.ts

@@ -45,7 +45,7 @@ function $ViewScrollProvider() {
     }
 
     return function ($element) {
-      $timeout(function () {
+      return $timeout(function () {
         $element[0].scrollIntoView();
       }, 0, false);
     };