Add the main frame routing ID to WebContentsDelegate, use it in BackgroundContents.

chrome/browser/background/background_contents_service.h

 // Copyright (c) 2012 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 CHROME_BROWSER_BACKGROUND_BACKGROUND_CONTENTS_SERVICE_H_
 #define CHROME_BROWSER_BACKGROUND_BACKGROUND_CONTENTS_SERVICE_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 91 matching lines @@
 
   // Creates a new BackgroundContents using the passed |site| and
   // the |route_id| and begins tracking the object internally so it can be
   // shutdown if the parent application is uninstalled.
   // A BACKGROUND_CONTENTS_OPENED notification will be generated with the passed
   // |frame_name| and |application_id| values, using the passed |profile| as the
   // Source..
   BackgroundContents* CreateBackgroundContents(
       content::SiteInstance* site,
       int route_id,
+      int main_frame_route_id,
       Profile* profile,
       const base::string16& frame_name,
       const base::string16& application_id,
       const std::string& partition_id,
       content::SessionStorageNamespace* session_storage_namespace);
 
   // Load the manifest-specified background page for the specified hosted app.
   // If the manifest doesn't specify one, then load the BackgroundContents
   // registered in the pref. This is typically used to reload a crashed
   // background page.
@@ skipping 113 matching lines @@
   BackgroundContentsMap contents_map_;
 
   ScopedObserver<extensions::ExtensionRegistry,
                  extensions::ExtensionRegistryObserver>
       extension_registry_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(BackgroundContentsService);
 };
 
 #endif  // CHROME_BROWSER_BACKGROUND_BACKGROUND_CONTENTS_SERVICE_H_