Delay request loading until all user scripts that request depends on are ready.

chrome/chrome.gyp

 # Copyright (c) 2009 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.
 
 {
   'variables': {
     'chromium_code': 1,
 
     # Define the common dependencies that contain all the actual
     # Chromium functionality.  This list gets pulled in below by
@@ skipping 1097 matching lines @@
         'browser/extensions/extensions_ui.h',
         'browser/extensions/external_extension_provider.h',
         'browser/extensions/external_registry_extension_provider_win.cc',
         'browser/extensions/external_registry_extension_provider_win.h',
         'browser/extensions/external_pref_extension_provider.cc',
         'browser/extensions/external_pref_extension_provider.h',
         'browser/extensions/sandboxed_extension_unpacker.cc',
         'browser/extensions/sandboxed_extension_unpacker.h',
         'browser/extensions/theme_preview_infobar_delegate.cc',
         'browser/extensions/theme_preview_infobar_delegate.h',
+        'browser/extensions/user_script_listener.cc',
+        'browser/extensions/user_script_listener.h',
         'browser/extensions/user_script_master.cc',
         'browser/extensions/user_script_master.h',
         'browser/external_protocol_handler.cc',
         'browser/external_protocol_handler.h',
         'browser/external_tab_container.cc',
         'browser/external_tab_container.h',
         'browser/global_keyboard_shortcuts_mac.h',
         'browser/global_keyboard_shortcuts_mac.mm',
         'browser/fav_icon_helper.cc',
         'browser/fav_icon_helper.h',
@@ skipping 2831 matching lines @@
         'browser/download/download_request_manager_unittest.cc',
         'browser/download/save_package_unittest.cc',
         'browser/encoding_menu_controller_unittest.cc',
         'browser/extensions/extension_file_util_unittest.cc',
         'browser/extensions/extension_l10n_util_unittest.cc',
         'browser/extensions/extension_messages_unittest.cc',
         'browser/extensions/extension_process_manager_unittest.cc',
         'browser/extensions/extension_ui_unittest.cc',
         'browser/extensions/extension_updater_unittest.cc',
         'browser/extensions/extensions_service_unittest.cc',
+        'browser/extensions/user_script_listener_unittest.cc',
         'browser/extensions/user_script_master_unittest.cc',
         'browser/find_backend_unittest.cc',
         'browser/first_run_migration_mac_unittest.mm',
         'browser/global_keyboard_shortcuts_mac_unittest.cc',
         'browser/google_url_tracker_unittest.cc',
         'browser/google_update_settings_posix_unittest.cc',
         'browser/gtk/bookmark_editor_gtk_unittest.cc',
         'browser/gtk/go_button_gtk_unittest.cc',
         'browser/gtk/options/cookies_view_unittest.cc',
         'browser/gtk/options/languages_page_gtk_unittest.cc',
@@ skipping 1850 matching lines @@
               # Use outputs of this action as inputs for the main target build.
               # Seems as a misnomer but makes this happy on Linux (scons).
               'process_outputs_as_sources': 1,
             },
           ],  # 'actions'
         },
       ]
     }],
   ],  # 'conditions'
 }