DevTools: add more jsdocs to NetworkPanel.

Source/devtools/front_end/elements/ElementsPanel.js

 /*
  * Copyright (C) 2007, 2008 Apple Inc.  All rights reserved.
  * Copyright (C) 2008 Matt Lilek <webkit@mattlilek.com>
  * Copyright (C) 2009 Joseph Pecoraro
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
@@ skipping 450 matching lines @@
     },
 
     _populateContextMenu: function(contextMenu, node)
     {
         // Add debbuging-related actions
         contextMenu.appendSeparator();
         var pane = WebInspector.domBreakpointsSidebarPane;
         pane.populateNodeContextMenu(node, contextMenu);
     },
 
-    _getPopoverAnchor: function(element)
+    /**
+     * @param {!Element} element
+     * @param {!Event} event
+     * @return {!Element|!AnchorBox|undefined}
+     */
+    _getPopoverAnchor: function(element, event)
     {
         var anchor = element.enclosingNodeOrSelfWithClass("webkit-html-resource-link");
         if (!anchor || !anchor.href)
-            return null;
+            return;
 
         var treeOutlineElement = anchor.enclosingNodeOrSelfWithClass("elements-tree-outline");
         if (!treeOutlineElement)
-            return null;
+            return;
 
         for (var i = 0; i < this._treeOutlines.length; ++i) {
             if (this._treeOutlines[i].element !== treeOutlineElement)
                 continue;
 
             var resource = this._treeOutlines[i].target().resourceTreeModel.resourceForURL(anchor.href);
             if (!resource || resource.type !== WebInspector.resourceTypes.Image)
-                return null;
+                return;
             anchor.removeAttribute("title");
             return anchor;
         }
-        return null;
     },
 
     /**
      * @param {!WebInspector.DOMNode} node
      * @param {function()} callback
      */
     _loadDimensionsForNode: function(node, callback)
     {
         if (!node.nodeName() || node.nodeName().toLowerCase() !== "img") {
             callback();
@@ skipping 969 matching lines @@
         /**
          * @suppressReceiverCheck
          * @this {Element}
          */
         function parentElement()
         {
             return this.parentElement;
         }
     }
 }