[Devtools] Fixes regression caused by experiment for network popover

third_party/WebKit/Source/devtools/front_end/network/NetworkWaterfallColumn.js

 // Copyright 2016 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.
 /**
  * @unrestricted
  */
 Network.NetworkWaterfallColumn = class extends UI.VBox {
   /**
    * @param {number} rowHeight
    * @param {!Network.NetworkTimeCalculator} calculator
@@ skipping 63 matching lines @@
   }
 
   /**
    * @param {!Element} element
    * @param {!Event} event
    * @return {!AnchorBox|undefined}
    */
   _getPopoverAnchor(element, event) {
     if (!this._hoveredNode)
       return;
+    var request = this._hoveredNode.request();
+    if (!request)
+      return;
     var useTimingBars = !Common.moduleSetting('networkColorCodeResourceTypes').get() && !this._calculator.startAtZero;
     if (useTimingBars) {
-      var request = this._hoveredNode.request();
-      if (!request)
-        return;
       var range = Network.RequestTimingView.calculateRequestTimeRanges(request, 0)
                       .find(data => data.name === Network.RequestTimeRangeNames.Total);
       var start = this._timeToPosition(range.start);
       var end = this._timeToPosition(range.end);
     } else {
-      var range = this._getSimplifiedBarRange(this.request(), 0);
+      var range = this._getSimplifiedBarRange(request, 0);
       var start = range.start;
       var end = range.end;
     }
 
     if (end - start < 50) {
       var halfWidth = (end - start) / 2;
       start = start + halfWidth - 25;
       end = end - halfWidth + 25;
     }
 
@@ skipping 521 matching lines @@
   font: 'hsl(8, 100%, 80%)',
   media: 'hsl(90, 50%, 80%)',
   image: 'hsl(90, 50%, 80%)',
   script: 'hsl(31, 100%, 80%)',
   stylesheet: 'hsl(272, 64%, 80%)',
   texttrack: 'hsl(8, 100%, 80%)',
   websocket: 'hsl(0, 0%, 95%)',
   xhr: 'hsl(53, 100%, 80%)',
   other: 'hsl(0, 0%, 95%)'
 };