Prevent duplicate concurrent installs of the same extension

chrome/chrome_browser_extensions.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': {
     # These variables are shared with the GN build.
     # Name is that these are the extensions files for the extensions target.
     # "chrome_browser_extensions_sources' are the extensions files in the
     # browser target.
     'chrome_browser_extensions_extensions_sources': [
       'browser/apps/ephemeral_app_service.cc',
       'browser/apps/ephemeral_app_service.h',
+      'browser/extensions/active_install_data.h',
+      'browser/extensions/active_install_data.cc',
       'browser/extensions/app_icon_loader.h',
       'browser/extensions/app_icon_loader_impl.cc',
       'browser/extensions/app_icon_loader_impl.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/blacklist.cc',
       'browser/extensions/blacklist.h',
       'browser/extensions/blacklist_state_fetcher.cc',
@@ skipping 1180 matching lines @@
       'type': 'static_library',
       'sources': [ 'browser/extensions/api/cast_channel/cast_channel.proto' ],
       'variables': {
           'proto_in_dir': 'browser/extensions/api/cast_channel',
           'proto_out_dir': 'chrome/browser/extensions/api/cast_channel',
       },
       'includes': [ '../build/protoc.gypi' ]
     },
   ],
 }