<webview>, <appview> and <extensionoptions> can run in a detached state.

extensions/renderer/resources/guest_view/guest_view.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This module implements a wrapper for a guestview that manages its
 // creation, attaching, and destruction.
 
 var GuestViewInternal =
     require('binding').Binding.create('guestViewInternal').generate();
 var GuestViewInternalNatives = requireNative('guest_view_internal');
@@ skipping 168 matching lines @@
     this.handleCallback(callback);
     return;
   }
 
   if (this.state == GUEST_STATE_START) {
     // destroy() does nothing in this case.
     this.handleCallback(callback);
     return;
   }
 
+  // If this guest is attached, then detach it first.
+  if (!!this.internalInstanceId) {
+    GuestViewInternalNatives.DetachGuest(this.internalInstanceId);
+  }
+
   GuestViewInternal.destroyGuest(this.id,
-                                 this.handleCallback.bind(this, callback));
+                                  this.handleCallback.bind(this, callback));

[paulmeyer, 2015/01/13 20:06:33]

Spacing; it looks like that extra space was a mistake.

[Fady Samuel, 2015/01/13 20:10:34]

Done.

 
   this.contentWindow = null;
   this.id = 0;
   this.internalInstanceId = 0;
   this.state = GUEST_STATE_START;
 };
 
 // Internal implementation of detach().
 GuestViewImpl.prototype.detachImpl = function(callback) {
   // Check the current state.
@@ skipping 78 matching lines @@
 };
 
 // Returns the ID for this guestview.
 GuestView.prototype.getId = function() {
   var internal = privates(this).internal;
   return internal.id;
 };
 
 // Exports
 exports.GuestView = GuestView;