[Extensions] Rework inline installation observation

chrome/chrome_common.gypi

 # Copyright (c) 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.
 
 {
   'variables': {
     # File lists shared with GN build.
     'chrome_common_sources': [
       'common/all_messages.h',
       'common/attrition_experiments.h',
@@ skipping 170 matching lines @@
       'common/extensions/manifest_handlers/ui_overrides_handler.cc',
       'common/extensions/manifest_handlers/ui_overrides_handler.h',
       'common/extensions/permissions/chrome_api_permissions.cc',
       'common/extensions/permissions/chrome_api_permissions.h',
       'common/extensions/permissions/chrome_permission_message_provider.cc',
       'common/extensions/permissions/chrome_permission_message_provider.h',
       'common/extensions/permissions/chrome_permission_message_rules.cc',
       'common/extensions/permissions/chrome_permission_message_rules.h',
       'common/extensions/sync_helper.cc',
       'common/extensions/sync_helper.h',
+      'common/extensions/webstore_install_result.cc',
+      'common/extensions/webstore_install_result.h',
     ],
     'chrome_common_printing_sources': [
       'common/chrome_utility_printing_messages.h',
       'common/cloud_print/cloud_print_cdd_conversion.cc',
       'common/cloud_print/cloud_print_cdd_conversion.h',
       'common/cloud_print/cloud_print_class_mac.h',
       'common/cloud_print/cloud_print_class_mac.mm',
       'common/cloud_print/cloud_print_constants.cc',
       'common/cloud_print/cloud_print_constants.h',
       'common/cloud_print/cloud_print_helpers.cc',
@@ skipping 476 matching lines @@
           ],
           'dependencies': [
             'installer_util',
             '../base/base.gyp:base',
           ],
         },
       ],
     }],
   ],
 }