Work around an AppKit bug that can leave two windows in a key state.

chrome/browser/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/chrome_build.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//build/split_static_library.gni")
 import("//chrome/common/features.gni")
@@ skipping 510 matching lines @@
     "mac/keystone_glue.h",
     "mac/keystone_glue.mm",
     "mac/keystone_registration.h",
     "mac/keystone_registration.mm",
     "mac/mac_startup_profiler.cc",
     "mac/mac_startup_profiler.h",
     "mac/master_prefs.h",
     "mac/master_prefs.mm",
     "mac/nsprocessinfo_additions.h",
     "mac/nsprocessinfo_additions.mm",
+    "mac/patch_nsmenu_key_window_bug.mm",
     "mac/relauncher.h",
     "mac/relauncher.mm",
     "mac/security_wrappers.cc",
     "mac/security_wrappers.h",
     "manifest/manifest_icon_downloader.cc",
     "manifest/manifest_icon_downloader.h",
     "manifest/manifest_icon_selector.cc",
     "manifest/manifest_icon_selector.h",
     "media/media_access_handler.h",
     "media/media_device_id_salt.cc",
@@ skipping 3988 matching lines @@
       "media/pepper_cdm_test_constants.cc",
       "media/pepper_cdm_test_constants.h",
     ]
   }
 }
 
 service_manifest("preferences_manifest") {
   name = "preferences"
   source = "prefs/preferences_manifest.json"
 }