Timeline: visually distinguish idle frames

Source/devtools/front_end/timeline/TimelineModel.js

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 39 matching lines @@
 WebInspector.TimelineModel.RecordType = {
     Task: "Task",
     Program: "Program",
     EventDispatch: "EventDispatch",
 
     GPUTask: "GPUTask",
 
     Animation: "Animation",
     RequestMainThreadFrame: "RequestMainThreadFrame",
     BeginFrame: "BeginFrame",
+    NeedsBeginFrameChanged: "NeedsBeginFrameChanged",
     BeginMainThreadFrame: "BeginMainThreadFrame",
     ActivateLayerTree: "ActivateLayerTree",
     DrawFrame: "DrawFrame",
     ScheduleStyleRecalculation: "ScheduleStyleRecalculation",
     RecalculateStyles: "RecalculateStyles", // For backwards compatibility only, now replaced by UpdateLayoutTree.
     UpdateLayoutTree: "UpdateLayoutTree",
     InvalidateLayout: "InvalidateLayout",
     Layout: "Layout",
     UpdateLayer: "UpdateLayer",
     UpdateLayerTree: "UpdateLayerTree",
@@ skipping 2004 matching lines @@
         /** @type {!Object.<string, !Array.<!WebInspector.InvalidationTrackingEvent>>} */
         this._invalidations = {};
         /** @type {!Object.<number, !Array.<!WebInspector.InvalidationTrackingEvent>>} */
         this._invalidationsByNodeId = {};
 
         this._lastRecalcStyle = undefined;
         this._lastPaintWithLayer = undefined;
         this._didPaint = false;
     }
 }