[DevTools] Move link click and context menu handling to Linkifier.

third_party/WebKit/Source/devtools/front_end/platform/DOMExtension.js

 /*
  * Copyright (C) 2007 Apple Inc.  All rights reserved.
  * 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 228 matching lines @@
     return /** @type {!Element} */ (node);
   if (node.nodeType === Node.DOCUMENT_FRAGMENT_NODE)
     return /** @type {!Element} */ (node.host);
   return null;
 };
 
 /**
  * @return {?Node}
  */
 Node.prototype.parentNodeOrShadowHost = function() {
-  return this.parentNode || this.host || null;
+  if (this.parentNode)
+    return this.parentNode;
+  if (this.nodeType === Node.DOCUMENT_FRAGMENT_NODE && this.host)
+    return this.host;
+  return null;
 };
 
 /**
  * @return {?Selection}
  */
 Node.prototype.getComponentSelection = function() {
   var parent = this.parentNode;
   while (parent && parent.nodeType !== Node.DOCUMENT_FRAGMENT_NODE)
     parent = parent.parentNode;
   return parent instanceof ShadowRoot ? parent.getSelection() : this.window().getSelection();
@@ skipping 554 matching lines @@
   function windowLoaded() {
     window.removeEventListener('DOMContentLoaded', windowLoaded, false);
     callback();
   }
 
   if (document.readyState === 'complete' || document.readyState === 'interactive')
     callback();
   else
     window.addEventListener('DOMContentLoaded', windowLoaded, false);
 }