Don't use GetAsTabContents. Send notifications from TabContentsView instead.

chrome/browser/tab_contents/background_contents.h

 // Copyright (c) 2010 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_TAB_CONTENTS_BACKGROUND_CONTENTS_H_
 #define CHROME_BROWSER_TAB_CONTENTS_BACKGROUND_CONTENTS_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 64 matching lines @@
                                     bool* did_suppress_message);
   virtual void Close(RenderViewHost* render_view_host);
   virtual RendererPreferences GetRendererPrefs(Profile* profile) const;
   virtual void RenderViewGone(RenderViewHost* rvh,
                               base::TerminationStatus status,
                               int error_code);
 
   // RenderViewHostDelegate::View
   virtual void CreateNewWindow(
       int route_id,
-      WindowContainerType window_container_type,
-      const string16& frame_name);
+      const ViewHostMsg_CreateWindow_Params& params);
   virtual void CreateNewWidget(int route_id, WebKit::WebPopupType popup_type);
   virtual void CreateNewFullscreenWidget(
       int route_id, WebKit::WebPopupType popup_type);
   virtual void ShowCreatedWindow(int route_id,
                                  WindowOpenDisposition disposition,
                                  const gfx::Rect& initial_pos,
                                  bool user_gesture);
   virtual void ShowCreatedWidget(int route_id,
                                  const gfx::Rect& initial_pos);
   virtual void ShowCreatedFullscreenWidget(int route_id);
@@ skipping 77 matching lines @@
   BackgroundContents* contents;
 
   // The name of the parent frame for these contents.
   const string16& frame_name;
 
   // The ID of the parent application (if any).
   const string16& application_id;
 };
 
 #endif  // CHROME_BROWSER_TAB_CONTENTS_BACKGROUND_CONTENTS_H_