Revert of DevTools: keep widgets in widget hierarchy upon hide, split attach/detach cycle from show/hide.

third_party/WebKit/Source/devtools/front_end/extensions/ExtensionPanel.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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 231 matching lines @@
     /**
      * @param {string} url
      */
     setPage: function(url)
     {
         if (this._objectPropertiesView) {
             this._objectPropertiesView.detach();
             delete this._objectPropertiesView;
         }
         if (this._extensionView)
-            this._extensionView.detach();
+            this._extensionView.detach(true);
 
         this._extensionView = new WebInspector.ExtensionView(this._server, this._id, url, "extension fill");
         this._extensionView.show(this.element);
 
         if (!this.element.style.height)
             this.setHeight("150px");
     },
 
     /**
      * @param {string} height
@@ skipping 16 matching lines @@
             callback(error.toString());
         else
             this._setObject(/** @type {!WebInspector.RemoteObject} */ (result), title, callback);
     },
 
     _createObjectPropertiesView: function()
     {
         if (this._objectPropertiesView)
             return;
         if (this._extensionView) {
-            this._extensionView.detach();
+            this._extensionView.detach(true);
             delete this._extensionView;
         }
         this._objectPropertiesView = new WebInspector.ExtensionNotifierView(this._server, this._id);
         this._objectPropertiesView.show(this.element);
     },
 
     /**
      * @param {!WebInspector.RemoteObject} object
      * @param {string} title
      * @param {function(?string=)} callback
@@ skipping 10 matching lines @@
         if (!title)
             section.titleLessMode();
         section.expand();
         section.editable = false;
         this._objectPropertiesView.element.appendChild(section.element);
         callback();
     },
 
     __proto__: WebInspector.View.prototype
 }