This patch improves the way that GuestViewManager tracks the destruction of GuestView embedders.

extensions/browser/guest_view/web_view/web_view_guest.h

 // 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.
 
 #ifndef EXTENSIONS_BROWSER_GUEST_VIEW_WEB_VIEW_WEB_VIEW_GUEST_H_
 #define EXTENSIONS_BROWSER_GUEST_VIEW_WEB_VIEW_WEB_VIEW_GUEST_H_
 
 #include <vector>
 
 #include "base/observer_list.h"
@@ skipping 24 matching lines @@
 // and manages the dispatch of <webview> extension events. WebViewGuest is
 // created on attachment. That is, when a guest WebContents is associated with
 // a particular embedder WebContents. This happens on either initial navigation
 // or through the use of the New Window API, when a new window is attached to
 // a particular <webview>.
 class WebViewGuest : public guest_view::GuestView<WebViewGuest>,
                      public content::NotificationObserver {
  public:
   // Clean up state when this GuestView is being destroyed. See
   // GuestViewBase::CleanUp().
-  static void CleanUp(int embedder_process_id, int view_instance_id);
+  static void CleanUp(content::BrowserContext* browser_context,
+                      int embedder_process_id,
+                      int view_instance_id);
 
   static GuestViewBase* Create(content::WebContents* owner_web_contents);
 
   // For WebViewGuest, we create special guest processes, which host the
   // tag content separately from the main application that embeds the tag.
   // A <webview> can specify both the partition name and whether the storage
   // for that partition should be persisted. Each tag gets a SiteInstance with
   // a specially formatted URL, based on the application it is hosted by and
   // the partition requested by it. The format for that URL is:
   // chrome-guest://partition_domain/persist?partition_name
@@ skipping 353 matching lines @@
   // This is used to ensure pending tasks will not fire after this object is
   // destroyed.
   base::WeakPtrFactory<WebViewGuest> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebViewGuest);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_GUEST_VIEW_WEB_VIEW_WEB_VIEW_GUEST_H_