DevTools: Do not linkify to pseudo (program) node when there's no URL

third_party/WebKit/Source/devtools/front_end/timeline/TimelineTreeView.js

 // Copyright 2015 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.
 
 /**
  * @constructor
  * @extends {WebInspector.VBox}
  * @param {!WebInspector.TimelineModel} model
  * @param {!Array<!WebInspector.TimelineModel.Filter>} filters
  */
@@ skipping 64 matching lines @@
      */
     _populateToolbar: function(parent) { },
 
     /**
      * @param {?WebInspector.TimelineProfileTree.Node} node
      */
     _onHover: function(node) { },
 
     /**
      * @param {!RuntimeAgent.CallFrame} frame
-     * @return {!Element}
+     * @return {?Element}
      */
     linkifyLocation: function(frame)
     {
         return this._linkifier.linkifyConsoleCallFrameForTimeline(this._model.target(), frame);
     },
 
     /**
      * @param {!WebInspector.TimelineProfileTree.Node} treeNode
      * @param {boolean} suppressSelectedEvent
      */
@@ skipping 244 matching lines @@
             var data = event.args["data"];
             var deoptReason = data && data["deoptReason"];
             if (deoptReason && deoptReason !== "no reason")
                 container.createChild("div", "activity-warning").title = WebInspector.UIString("Not optimized: %s", deoptReason);
             name.textContent = event.name === WebInspector.TimelineModel.RecordType.JSFrame
                 ? WebInspector.beautifyFunctionName(event.args["data"]["functionName"])
                 : WebInspector.TimelineUIUtils.eventTitle(event);
             var frame = WebInspector.TimelineProfileTree.eventStackFrame(event);
             if (frame && frame["url"]) {
                 var callFrame = /** @type {!RuntimeAgent.CallFrame} */ (frame);
-                container.createChild("div", "activity-link").appendChild(this._treeView.linkifyLocation(callFrame));
+                var link = this._treeView.linkifyLocation(callFrame);
+                if (link)
+                    container.createChild("div", "activity-link").appendChild(link);
             }
             icon.style.backgroundColor = WebInspector.TimelineUIUtils.eventColor(event);
         }
         return cell;
     },
 
     /**
      * @param {string} columnIdentifier
      * @return {?Element}
      */
@@ skipping 516 matching lines @@
         return selectedNode && /** @type {!WebInspector.TimelineTreeView.GridNode} */ (selectedNode)._profileNode;
     },
 
     _onSelectionChanged: function()
     {
         this.dispatchEventToListeners(WebInspector.TimelineStackView.Events.SelectionChanged);
     },
 
     __proto__: WebInspector.VBox.prototype
 }