Remove the RenderProcessHost observer and attach the WebContentsObserver earlier to the GuestView.

extensions/browser/guest_view/guest_view_manager.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_GUEST_VIEW_MANAGER_H_
 #define EXTENSIONS_BROWSER_GUEST_VIEW_GUEST_VIEW_MANAGER_H_
 
 #include <map>
 
 #include "base/gtest_prod_util.h"
@@ skipping 54 matching lines @@
       WebContentsCreatedCallback;
   void CreateGuest(const std::string& view_type,
                    const std::string& embedder_extension_id,
                    content::WebContents* embedder_web_contents,
                    const base::DictionaryValue& create_params,
                    const WebContentsCreatedCallback& callback);
 
   content::WebContents* CreateGuestWithWebContentsParams(
       const std::string& view_type,
       const std::string& embedder_extension_id,
-      int embedder_render_process_id,
+      content::WebContents* embedder_web_contents,
       const content::WebContents::CreateParams& create_params);
 
   content::SiteInstance* GetGuestSiteInstance(
       const GURL& guest_site);
 
   // BrowserPluginGuestManager implementation.
   virtual content::WebContents* GetGuestByInstanceID(
       content::WebContents* embedder_web_contents,
       int element_instance_id) override;
   virtual bool ForEachGuest(content::WebContents* embedder_web_contents,
@@ skipping 63 matching lines @@
   std::set<int> removed_instance_ids_;
 
   content::BrowserContext* context_;
 
   DISALLOW_COPY_AND_ASSIGN(GuestViewManager);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_GUEST_VIEW_GUEST_VIEW_MANAGER_H_