DevTools: move session logic from TracingModel to TimelineModel

Source/devtools/front_end/timeline/TimelinePanel.js

 /*
  * Copyright (C) 2012 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 224 matching lines @@
         this._overviewPane.requestWindowTimes(windowStartTime, windowEndTime);
     },
 
     /**
      * @return {!WebInspector.TimelineFrameModelBase}
      */
     _frameModel: function()
     {
         if (!this._lazyFrameModel) {
             var tracingFrameModel = new WebInspector.TracingTimelineFrameModel();
-            tracingFrameModel.addTraceEvents(this._model.target(), this._model.inspectedTargetEvents(), this._tracingModel.sessionId() || "");
+            tracingFrameModel.addTraceEvents(this._model.target(), this._model.inspectedTargetEvents(), this._model.sessionId() || "");
             this._lazyFrameModel = tracingFrameModel;
         }
         return this._lazyFrameModel;
     },
 
     /**
      * @return {!WebInspector.Widget}
      */
     _layersView: function()
     {
@@ skipping 593 matching lines @@
             this._helpMessageElement.remove();
         delete this._helpMessageElement;
     },
 
     _onRecordingStopped: function()
     {
         this._stopPending = false;
         this._updateToggleTimelineButton(false);
         if (this._lazyFrameModel) {
             this._lazyFrameModel.reset();
-            this._lazyFrameModel.addTraceEvents(this._model.target(), this._model.inspectedTargetEvents(), this._tracingModel.sessionId());
+            this._lazyFrameModel.addTraceEvents(this._model.target(), this._model.inspectedTargetEvents(), this._model.sessionId());
         }
         this._overviewPane.reset();
         this._overviewPane.setBounds(this._model.minimumRecordTime(), this._model.maximumRecordTime());
         this.requestWindowTimes(this._model.minimumRecordTime(), this._model.maximumRecordTime());
         this._refreshViews();
         for (var i = 0; i < this._overviewControls.length; ++i)
             this._overviewControls[i].timelineStopped();
         this._setMarkers();
         this._overviewPane.scheduleUpdate();
         this._updateSearchHighlight(false, true);
@@ skipping 1054 matching lines @@
      * @param {!WebInspector.Context} context
      * @param {string} actionId
      */
     handleAction: function(context, actionId)
     {
         var panel = WebInspector.context.flavor(WebInspector.TimelinePanel);
         console.assert(panel && panel instanceof WebInspector.TimelinePanel);
         panel._toggleTimelineButtonClicked();
     }
 }