DevTools: merge TracingTimelineModel into TimelineModel

Source/devtools/front_end/timeline/TimelineView.js

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  * Copyright (C) 2012 Intel 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.
@@ skipping 159 matching lines @@
             frameStrip._frame = frame;
             this._frameStripByFrame.set(frame, frameStrip);
 
             const minWidthForFrameInfo = 60;
             if (width > minWidthForFrameInfo)
                 frameStrip.textContent = Number.millisToString(frame.endTime - frame.startTime, true);
 
             this._frameContainer.appendChild(frameStrip);
 
             if (actualStart > 0) {
-                var frameMarker = WebInspector.TimelineUIUtils.createEventDivider(WebInspector.TracingTimelineModel.RecordType.BeginFrame);
+                var frameMarker = WebInspector.TimelineUIUtils.createEventDivider(WebInspector.TimelineModel.RecordType.BeginFrame);
                 frameMarker.style.left = frameStart + "px";
                 dividers.push(frameMarker);
             }
         }
         this._timelineGrid.addEventDividers(dividers);
         this._headerElement.appendChild(this._frameContainer);
     },
 
     _onFrameDoubleClicked: function(event)
     {
@@ skipping 1097 matching lines @@
         } else {
             this._element.classList.add("hidden");
         }
     },
 
     _dispose: function()
     {
         this._element.remove();
     }
 }