Implement the inert attribute

third_party/WebKit/Source/core/dom/Node.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004-2011, 2014 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 526 matching lines @@
   virtual void SetActive(bool flag = true);
   virtual void SetDragged(bool flag);
   virtual void SetHovered(bool flag = true);
 
   virtual int tabIndex() const;
 
   virtual Node* FocusDelegate();
   // This is called only when the node is focused.
   virtual bool ShouldHaveFocusAppearance() const;
 
-  // Whether the node is inert. This can't be in Element because text nodes
-  // must be recognized as inert to prevent text selection.
+  // Whether the node is inert:
+  // https://html.spec.whatwg.org/multipage/interaction.html#inert
+  // https://github.com/WICG/inert/blob/master/README.md
+  // This can't be in Element because text nodes must be recognized as
+  // inert to prevent text selection.
   bool IsInert() const;
 
   virtual LayoutRect BoundingBox() const;
   IntRect PixelSnappedBoundingBox() const {
     return PixelSnappedIntRect(BoundingBox());
   }
 
   unsigned NodeIndex() const;
 
   // Returns the DOM ownerDocument attribute. This method never returns null,
@@ skipping 485 matching lines @@
 }  // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showNode(const blink::Node*);
 void showTree(const blink::Node*);
 void showNodePath(const blink::Node*);
 #endif
 
 #endif  // Node_h