Implement the inert attribute

third_party/WebKit/Source/core/html/HTMLElement.idl

 /*
  * Copyright (C) 2006, 2007, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Samuel Weinig <sam.weinig@gmail.com>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 14 matching lines @@
     [CEReactions, Reflect] attribute DOMString title;
     [CEReactions, Reflect] attribute DOMString lang;
     [CEReactions] attribute boolean translate;
     [CEReactions] attribute DOMString dir;
     [SameObject, PerWorldBindings] readonly attribute DOMStringMap dataset;
 
     // user interaction
     [CEReactions, Reflect] attribute boolean hidden;
     [ImplementedAs=clickForBindings] void click();
     [CEReactions, CustomElementCallbacks] attribute long tabIndex;
+    [RuntimeEnabled=InertAttribute, Reflect] attribute boolean inert;
     void focus();
     void blur();
     [CEReactions, Reflect] attribute DOMString accessKey;
     [CEReactions, CustomElementCallbacks] attribute boolean draggable;
     [CEReactions, RuntimeEnabled=ContextMenu] attribute HTMLMenuElement? contextMenu;
     [CEReactions] attribute boolean spellcheck;
 
     // HTMLElement implements ElementContentEditable
     // https://html.spec.whatwg.org/#contenteditable
     [CEReactions, CustomElementCallbacks, RaisesException=Setter] attribute DOMString contentEditable;
@@ skipping 14 matching lines @@
     // https://drafts.css-houdini.org/css-typed-om/#inline-stylepropertymap-objects
     [RuntimeEnabled=CSSTypedOM] readonly attribute StylePropertyMap styleMap;
 
     // Non-standard APIs
     [TreatNullAs=NullString, CustomElementCallbacks, RaisesException=Setter, MeasureAs=HTMLElementInnerText] attribute DOMString innerText;
     [TreatNullAs=NullString, CustomElementCallbacks, RaisesException=Setter, MeasureAs=HTMLElementOuterText] attribute DOMString outerText;
     [CEReactions, Reflect, TreatNullAs=NullString, MeasureAs=PrefixedHTMLElementDropzone] attribute DOMString webkitdropzone;
 };
 
 HTMLElement implements GlobalEventHandlers;