Introduce background.scripts feature for extension manifests.

chrome/common/extensions/extension_file_util.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/common/extensions/extension_file_util.h"
 
 #include <map>
 #include <vector>
 
 #include "base/file_util.h"
@@ skipping 273 matching lines @@
             l10n_util::GetStringFUTF8(
                 IDS_EXTENSION_LOAD_ICON_FOR_BROWSER_ACTION_FAILED,
                 UTF8ToUTF16(path));
         return false;
     }
   }
 
   // Validate background page location, except for hosted apps, which should use
   // an external URL. Background page for hosted apps are verified when the
   // extension is created (in Extension::InitFromValue)
-  if (!extension->background_url().is_empty() && !extension->is_hosted_app()) {
+  if (extension->has_background_page() &&
+      !extension->is_hosted_app() &&
+      extension->background_scripts().empty()) {
     FilePath page_path = ExtensionURLToRelativeFilePath(
-        extension->background_url());
+        extension->GetBackgroundURL());
     const FilePath path = extension->GetResource(page_path).GetFilePath();
     if (path.empty() || !file_util::PathExists(path)) {
       *error =
           l10n_util::GetStringFUTF8(
               IDS_EXTENSION_LOAD_BACKGROUND_PAGE_FAILED,
               page_path.LossyDisplayName());
       return false;
     }
   }
 
@@ skipping 358 matching lines @@
     return temp_path;
 
   return FilePath();
 }
 
 void DeleteFile(const FilePath& path, bool recursive) {
   file_util::Delete(path, recursive);
 }
 
 }  // namespace extension_file_util