Delete dead AppsPromo code

chrome/chrome_browser_extensions.gypi

 # 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.
 
 {
   'targets': [
     {
       'target_name': 'browser_extensions',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
@@ skipping 214 matching lines @@
         'browser/extensions/app_notification_manager.cc',
         'browser/extensions/app_notification_manager.h',
         'browser/extensions/app_notification_storage.cc',
         'browser/extensions/app_notification_storage.h',
         'browser/extensions/app_notify_channel_setup.cc',
         'browser/extensions/app_notify_channel_setup.h',
         'browser/extensions/app_notify_channel_ui.cc',
         'browser/extensions/app_notify_channel_ui.h',
         'browser/extensions/app_shortcut_manager.cc',
         'browser/extensions/app_shortcut_manager.h',
-        'browser/extensions/apps_promo.cc',
-        'browser/extensions/apps_promo.h',
         'browser/extensions/app_sync_bundle.cc',
         'browser/extensions/app_sync_bundle.h',
         'browser/extensions/app_sync_data.cc',
         'browser/extensions/app_sync_data.h',
         'browser/extensions/browser_action_test_util.h',
         'browser/extensions/browser_action_test_util_gtk.cc',
         'browser/extensions/browser_action_test_util_mac.mm',
         'browser/extensions/browser_extension_window_controller.cc',
         'browser/extensions/browser_extension_window_controller.h',
         'browser/extensions/bundle_installer.cc',
@@ skipping 447 matching lines @@
             'browser/extensions/api/usb/usb_api.h',
             'browser/extensions/api/usb/usb_device_resource.cc',
             'browser/extensions/api/usb/usb_device_resource.h',
           ],
         }],
       ],
     },
   ],
 }