Move requestAnimationFrame fallback to own module

app/assets/javascripts/awards_handler.js

@@ -10,14 +10,10 @@ import { isInVueNoteablePage } from './lib/utils/dom_utils';
 import flash from './flash';
 import axios from './lib/utils/axios_utils';
 import * as Emoji from '~/emoji';
+import requestAnimationFrame from '~/lib/utils/request_animation_frame_fallback';
 
 const animationEndEventString = 'animationend webkitAnimationEnd MSAnimationEnd oAnimationEnd';
 const transitionEndEventString = 'transitionend webkitTransitionEnd oTransitionEnd MSTransitionEnd';
-const requestAnimationFrame =
-  window.requestAnimationFrame ||
-  window.webkitRequestAnimationFrame ||
-  window.mozRequestAnimationFrame ||
-  window.setTimeout;
 
 const FROM_SENTENCE_REGEX = /(?:, and | and |, )/; // For separating lists produced by ruby's Array#toSentence
 

app/assets/javascripts/lib/utils/request_animation_frame_fallback.js

+/**
+ * DO NOT USE!
+ *
+ * This is a module meant to encapsulate a legacy bit of calculation so that it can
+ * be easily mocked in Jest to fix performance and degredation issues.
+ */
+export default window.requestAnimationFrame ||
+  window.webkitRequestAnimationFrame ||
+  window.mozRequestAnimationFrame ||
+  window.setTimeout;