app_shell: Make renderer run background page JavaScript

apps/shell/shell_browser_main_parts.h

 // 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.
 
 #ifndef APPS_SHELL_SHELL_BROWSER_MAIN_PARTS_H_
 #define APPS_SHELL_SHELL_BROWSER_MAIN_PARTS_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 28 matching lines @@
                               public aura::RootWindowObserver {
  public:
   explicit ShellBrowserMainParts(
       const content::MainFunctionParams& parameters);
   virtual ~ShellBrowserMainParts();
 
   ShellBrowserContext* browser_context() {
     return browser_context_.get();
   }
 
+  extensions::ShellExtensionSystem* extension_system() {
+    return extension_system_;
+  }
+
   // BrowserMainParts overrides.
   virtual void PreEarlyInitialization() OVERRIDE;
   virtual void PreMainMessageLoopStart() OVERRIDE;
   virtual void PostMainMessageLoopStart() OVERRIDE;
   virtual int PreCreateThreads() OVERRIDE;
   virtual void PreMainMessageLoopRun() OVERRIDE;
   virtual bool MainMessageLoopRun(int* result_code) OVERRIDE;
   virtual void PostMainMessageLoopRun() OVERRIDE;
 
   // aura::RootWindowObserver overrides:
@@ skipping 22 matching lines @@
 
   // Owned by the BrowserContextKeyedService system.
   extensions::ShellExtensionSystem* extension_system_;
 
   DISALLOW_COPY_AND_ASSIGN(ShellBrowserMainParts);
 };
 
 }  // namespace apps
 
 #endif  // APPS_SHELL_SHELL_BROWSER_MAIN_PARTS_H_