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

content/shell/browser/shell.cc

 // Copyright 2013 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 "content/shell/browser/shell.h"
 
 #include "base/auto_reset.h"
 #include "base/command_line.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 136 matching lines @@
 
 gfx::Size Shell::AdjustWindowSize(const gfx::Size& initial_size) {
   if (!initial_size.IsEmpty())
     return initial_size;
   return gfx::Size(kDefaultTestWindowWidthDip, kDefaultTestWindowHeightDip);
 }
 
 Shell* Shell::CreateNewWindow(BrowserContext* browser_context,
                               const GURL& url,
                               SiteInstance* site_instance,
-                              int routing_id,
                               const gfx::Size& initial_size) {
   WebContents::CreateParams create_params(browser_context, site_instance);
-  create_params.routing_id = routing_id;
   create_params.initial_size = AdjustWindowSize(initial_size);
   WebContents* web_contents = WebContents::Create(create_params);
   Shell* shell = CreateShell(web_contents, create_params.initial_size);
   if (!url.is_empty())
     shell->LoadURL(url);
   return shell;
 }
 
 void Shell::LoadURL(const GURL& url) {
   LoadURLForFrame(url, std::string());
@@ skipping 229 matching lines @@
   devtools_frontend_->Activate();
   devtools_frontend_->Focus();
 }
 
 void Shell::OnDevToolsWebContentsDestroyed() {
   devtools_observer_.reset();
   devtools_frontend_ = NULL;
 }
 
 }  // namespace content