[MD Bookmarks] Refactor window timer mocking.

chrome/browser/resources/md_bookmarks/dnd_manager.js

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 cr.define('bookmarks', function() {
   /**
    * @param {BookmarkElement} element
    * @return {boolean}
    */
   function isBookmarkItem(element) {
@@ skipping 168 matching lines @@
 
   /**
    * Encapsulates the behavior of the drag and drop indicator which puts a line
    * between items or highlights folders which are valid drop targets.
    * @constructor
    */
   function DropIndicator() {
     /**
      * @private {number|null} Timer id used to help minimize flicker.
      */
-    this.removeDropIndicatorTimer_ = null;
+    this.removeDropIndicatorTimeoutId_ = null;
 
     /**
      * The element that had a style applied it to indicate the drop location.
      * This is used to easily remove the style when necessary.
      * @private {BookmarkElement|null}
      */
     this.lastIndicatorElement_ = null;
 
     /**
      * The style that was applied to indicate the drop location.
      * @private {?string|null}
      */
     this.lastIndicatorClassName_ = null;
 
     /**
      * Used to instantly remove the indicator style in tests.
-     * @private {function((Function|null|string), number)}
+     * @private {bookmarks.TimerProxy}
      */
-    this.setTimeout = window.setTimeout.bind(window);
+    this.timerProxy = new bookmarks.TimerProxy();
   }
 
   DropIndicator.prototype = {
     /**
      * Applies the drop indicator style on the target element and stores that
      * information to easily remove the style in the future.
      * @param {HTMLElement} indicatorElement
      * @param {DropPosition} position
      */
     addDropIndicatorStyle: function(indicatorElement, position) {
@@ skipping 18 matching lines @@
       this.lastIndicatorElement_ = null;
       this.lastIndicatorClassName_ = null;
     },
 
     /**
      * Displays the drop indicator on the current drop target to give the
      * user feedback on where the drop will occur.
      * @param {DropDestination} dropDest
      */
     update: function(dropDest) {
-      window.clearTimeout(this.removeDropIndicatorTimer_);
+      this.timerProxy.clearTimeout(this.removeDropIndicatorTimeoutId_);
 
       var indicatorElement = dropDest.element.getDropTarget();
       var position = dropDest.position;
 
       this.removeDropIndicatorStyle();
       this.addDropIndicatorStyle(indicatorElement, position);
     },
 
     /**
      * Stop displaying the drop indicator.
      */
     finish: function() {
       // The use of a timeout is in order to reduce flickering as we move
       // between valid drop targets.
-      window.clearTimeout(this.removeDropIndicatorTimer_);
-      this.removeDropIndicatorTimer_ = this.setTimeout(function() {
-        this.removeDropIndicatorStyle();
-      }.bind(this), 100);
+      this.timerProxy.clearTimeout(this.removeDropIndicatorTimeoutId_);
+      this.removeDropIndicatorTimeoutId_ =
+          this.timerProxy.setTimeout(function() {
+            this.removeDropIndicatorStyle();
+          }.bind(this), 100);
     },
   };
 
   /**
    * Manages drag and drop events for the bookmarks-app.
    * @constructor
    */
   function DNDManager() {
     /** @private {bookmarks.DragInfo} */
     this.dragInfo_ = null;
 
     /** @private {?DropDestination} */
     this.dropDestination_ = null;
 
     /** @private {bookmarks.DropIndicator} */
     this.dropIndicator_ = null;
 
     /** @private {Object<string, function(!Event)>} */
     this.documentListeners_ = null;
 
     /**
      * Used to instantly clearDragData in tests.
-     * @private {function((Function|null|string), number)}
+     * @private {bookmarks.TimerProxy}
      */
-    this.setTimeout_ = window.setTimeout.bind(window);
+    this.timerProxy_ = new bookmarks.TimerProxy();
   }
 
   DNDManager.prototype = {
     init: function() {
       this.dragInfo_ = new DragInfo();
       this.dropIndicator_ = new DropIndicator();
       this.autoExpander_ = new AutoExpander();
 
       this.documentListeners_ = {
         'dragstart': this.onDragStart_.bind(this),
@@ skipping 78 matching lines @@
         index: index,
         parentId: parentId,
       };
     },
 
     /** @private */
     clearDragData_: function() {
       // Defer the clearing of the data so that the bookmark manager API's drop
       // event doesn't clear the drop data before the web drop event has a
       // chance to execute (on Mac).
-      this.setTimeout_(function() {
+      this.timerProxy_.setTimeout(function() {
         this.dragInfo_.clearDragData();
         this.dropDestination_ = null;
         this.dropIndicator_.finish();
       }.bind(this), 0);
     },
 
     /**
      * @private
      * @param {Event} e
      */
@@ skipping 231 matching lines @@
             state.nodes[state.selectedFolder].children.length == 0;
       }
 
       // We can only drop on a folder.
       if (getBookmarkNode(overElement).url)
         return false;
 
       return !this.dragInfo_.isDraggingChildBookmark(overElement.itemId);
     },
 
-    disableTimeoutsForTesting: function() {
-      this.setTimeout_ = function(fn) {
-        fn();
-      };
-      this.dropIndicator_.setTimeout = this.setTimeout_;
+    /** @param {bookmarks.TimerProxy} timerProxy */
+    setTimerProxyForTesting: function(timerProxy) {
+      this.timerProxy_ = timerProxy;
+      this.dropIndicator_.timerProxy = timerProxy;
     }
   };
 
   return {
     DNDManager: DNDManager,
     DragInfo: DragInfo,
     DropIndicator: DropIndicator,
   };
 });