Devtools Animations: Don't wait for empty transitions to start

third_party/WebKit/Source/devtools/front_end/animation/AnimationModel.js

 // Copyright (c) 2014 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.
 
 
 /**
  * @constructor
  * @extends {WebInspector.SDKModel}
  * @param {!WebInspector.Target} target
  */
 WebInspector.AnimationModel = function(target)
 {
     WebInspector.SDKModel.call(this, WebInspector.AnimationModel, target);
     this._agent = target.animationAgent();
     target.registerAnimationDispatcher(new WebInspector.AnimationDispatcher(this));
     /** @type {!Map.<string, !WebInspector.AnimationModel.Animation>} */
     this._animationsById = new Map();
     /** @type {!Map.<string, !WebInspector.AnimationModel.AnimationGroup>} */
     this._animationGroups = new Map();
     /** @type {!Array.<string>} */
     this._pendingAnimations = [];
     target.resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.MainFrameNavigated, this._mainFrameNavigated, this);
 }
 
 WebInspector.AnimationModel.Events = {
-    AnimationGroupStarted: "AnimationGroupStarted",
-    AnimationCanceled: "AnimationCanceled"
+    AnimationGroupStarted: "AnimationGroupStarted"
 }
 
 WebInspector.AnimationModel.prototype = {
     _mainFrameNavigated: function()
     {
         this._animationsById.clear();
         this._animationGroups.clear();
         this._pendingAnimations = [];
     },
 
     /**
      * @param {string} id
      */
     animationCreated: function(id)
     {
         this._pendingAnimations.push(id);
     },
 
+    _animationCancelled: function(id)
+    {
+        this._pendingAnimations.remove(id);
+        this._flushPendingAnimationsIfNeeded();
+    },
+
     /**
      * @param {!AnimationAgent.Animation} payload
      */
     animationStarted: function(payload)
     {
         var animation = WebInspector.AnimationModel.Animation.parsePayload(this.target(), payload);
         this._animationsById.set(animation.id(), animation);
+        this._flushPendingAnimationsIfNeeded();
+    },
 
+    _flushPendingAnimationsIfNeeded: function()
+    {
         for (var id of this._pendingAnimations) {
             if (!this._animationsById.get(id))
                 return;
         }
 
         while (this._pendingAnimations.length)
             this._matchExistingGroups(this._createGroupFromPendingAnimations());
     },
 
     /**
@@ skipping 681 matching lines @@
      * @override
      * @param {string} id
      */
     animationCreated: function(id)
     {
         this._animationModel.animationCreated(id);
     },
 
     /**
      * @override
+     * @param {string} id
+     */
+    animationCancelled: function(id)
+    {
+        this._animationModel._animationCancelled(id);
+    },
+
+    /**
+     * @override
      * @param {!AnimationAgent.Animation} payload
      */
     animationStarted: function(payload)
     {
         this._animationModel.animationStarted(payload);
     }
 }