[DevTools] Rework some focus code.

third_party/WebKit/Source/devtools/front_end/sources/NavigatorView.js

 /*
  * Copyright (C) 2012 Google 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:
  *
  * 1. Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *
@@ skipping 960 matching lines @@
         {
             this._warmedUpContent = content;
         }
     },
 
     _shouldRenameOnMouseDown: function()
     {
         if (!this._uiSourceCode.canRename())
             return false;
         var isSelected = this === this.treeOutline.selectedTreeElement;
-        var document = this.treeOutline.element.ownerDocument;
-        var isFocused = this.treeOutline.element.isSelfOrAncestor(document.activeElement);
-        return isSelected && isFocused && !WebInspector.isBeingEdited(this.treeOutline.element);
+        return isSelected && this.treeOutline.element.hasFocus() && !WebInspector.isBeingEdited(this.treeOutline.element);
     },
 
     selectOnMouseDown: function(event)
     {
         if (event.which !== 1 || !this._shouldRenameOnMouseDown()) {
             TreeElement.prototype.selectOnMouseDown.call(this, event);
             return;
         }
         setTimeout(rename.bind(this), 300);
 
@@ skipping 639 matching lines @@
             return;
         this._treeElement.listItemElement.classList.toggle("has-mapped-files", isActive);
         if (isActive)
             this._treeElement.expand();
         else
             this._treeElement.collapse();
     },
 
     __proto__: WebInspector.NavigatorTreeNode.prototype
 }