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

extensions/browser/guest_view/extension_options/extension_options_guest.cc

 // 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.
 
 #include "extensions/browser/guest_view/extension_options/extension_options_guest.h"
 
 #include "base/metrics/user_metrics.h"
 #include "base/values.h"
 #include "components/crx_file/id_util.h"
 #include "content/public/browser/navigation_details.h"
@@ skipping 194 matching lines @@
     const content::ContextMenuParams& params) {
   if (!extension_options_guest_delegate_)
     return false;
 
   return extension_options_guest_delegate_->HandleContextMenu(params);
 }
 
 bool ExtensionOptionsGuest::ShouldCreateWebContents(
     content::WebContents* web_contents,
     int route_id,
+    int main_frame_route_id,
     WindowContainerType window_container_type,
     const base::string16& frame_name,
     const GURL& target_url,
     const std::string& partition_id,
     content::SessionStorageNamespace* session_storage_namespace) {
   // This method handles opening links from within the guest. Since this guest
   // view is used for displaying embedded extension options, we want any
   // external links to be opened in a new tab, not in a new guest view.
   // Therefore we just open the URL in a new tab, and since we aren't handling
   // the new web contents, we return false.
@@ skipping 54 matching lines @@
   attach_params()->GetInteger(extensionoptions::kAttributeMinWidth, &min_width);
 
   // Call SetAutoSize to apply all the appropriate validation and clipping of
   // values.
   SetAutoSize(auto_size_enabled,
               gfx::Size(min_width, min_height),
               gfx::Size(max_width, max_height));
 }
 
 }  // namespace extensions