Fix exception when selecting record in timeline based on trace events

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 946 matching lines @@
 
     _updateSelectionDetails: function()
     {
         if (!this._selection) {
             this._updateSelectedRangeStats();
             return;
         }
         switch (this._selection.type()) {
         case WebInspector.TimelineSelection.Type.Record:
             var record = /** @type {!WebInspector.TimelineModel.Record} */ (this._selection.object());
-            WebInspector.TimelineUIUtils.generatePopupContent(record, this._model, this._detailsLinkifier, this.showInDetails.bind(this, record.title()), this._model.loadedFromFile());
+            if (this._tracingTimelineModel) {
+                var event = this._tracingTimelineModel.traceEventFrom(record);
+                this._buildSelectionDetailsForTraceEvent(event);
+            } else {
+                WebInspector.TimelineUIUtils.generatePopupContent(record, this._model, this._detailsLinkifier, this.showInDetails.bind(this, record.title()), this._model.loadedFromFile());
+            }
             break;
         case WebInspector.TimelineSelection.Type.TraceEvent:
             var event = /** @type {!WebInspector.TracingModel.Event} */ (this._selection.object());
-            var title = WebInspector.TimelineUIUtils.styleForTimelineEvent(event.name).title;
-            var tracingModel = this._tracingTimelineModel;
-            WebInspector.TracingTimelineUIUtils.buildTraceEventDetails(event, tracingModel, this._detailsLinkifier, this.showInDetails.bind(this, title), false, this._model.target());
+            this._buildSelectionDetailsForTraceEvent(event);
             break;
         case WebInspector.TimelineSelection.Type.Frame:
             var frame = /** @type {!WebInspector.TimelineFrame} */ (this._selection.object());
             if (frame.layerTree) {
                 var layersView = this._layersView();
                 layersView.showLayerTree(frame.layerTree);
                 this._detailsView.setChildView(WebInspector.UIString("Frame Layers"), layersView);
             } else {
                 this.showInDetails(WebInspector.UIString("Frame Statistics"), WebInspector.TimelineUIUtils.generatePopupContentForFrame(this._lazyFrameModel, frame));
             }
             break;
         }
     },
 
+    /**
+     * @param {!WebInspector.TracingModel.Event} event
+     */
+    _buildSelectionDetailsForTraceEvent: function(event)
+    {
+        var title = WebInspector.TimelineUIUtils.styleForTimelineEvent(event.name).title;
+        WebInspector.TracingTimelineUIUtils.buildTraceEventDetails(event, this._tracingTimelineModel, this._detailsLinkifier, this.showInDetails.bind(this, title), false, this._model.target());
+    },
+
     _updateSelectedRangeStats: function()
     {
         if (this._selection)
             return;
 
         var startTime = this._windowStartTime;
         var endTime = this._windowEndTime;
 
         // Return early in case 0 selection window.
         if (startTime < 0)
@@ skipping 425 matching lines @@
      * @param {!WebInspector.TimelineModel.Record} record
      * @return {boolean}
      */
     accept: function(record)
     {
         return !this._hiddenRecords[record.type()];
     },
 
     __proto__: WebInspector.TimelineModel.Filter.prototype
 }