Introduce background.scripts feature for extension manifests.

chrome/browser/extensions/extension_event_router.cc

 // 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.
 
 #include "chrome/browser/extensions/extension_event_router.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/values.h"
 #include "chrome/browser/extensions/extension_devtools_manager.h"
@@ skipping 206 matching lines @@
           switches::kEnableLazyBackgroundPages))
     return true;
 
   if (extension_id.empty())
     // TODO(tessamac): Create all background pages. Wait for all to be loaded?
     //                 or dispatch event to each extension when it's ready?
     return true;
 
   const Extension* extension = profile_->GetExtensionService()->
       GetExtensionById(extension_id, false);  // exclude disabled extensions
-  if (extension && extension->background_url().is_valid()) {
+  if (extension && extension->has_background_page()) {
     ExtensionProcessManager* pm = profile_->GetExtensionProcessManager();
     if (!pm->GetBackgroundHostForExtension(extension_id)) {
-      pm->CreateBackgroundHost(extension, extension->background_url());
+      pm->CreateBackgroundHost(extension, extension->GetBackgroundURL());
       return false;
     }
   }
 
   return true;
 }
 
 void ExtensionEventRouter::DispatchEventImpl(
     const linked_ptr<ExtensionEvent>& event, bool was_pending) {
   if (!profile_)
@@ skipping 151 matching lines @@
       ExtensionHost* eh = content::Details<ExtensionHost>(details).ptr();
       DispatchPendingEvents(eh->extension_id());
       break;
     }
     // TODO(tessamac): if background page crashed/failed clear queue.
     default:
       NOTREACHED();
       return;
   }
 }