Use ICU for string pluralization in the extension permission dialog.

ui/ui.gyp

 # 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.
 
 {
   'variables': {
     'chromium_code': 1,
   },
   'includes': [
     'shell_dialogs.gypi',
@@ skipping 197 matching lines @@
         'base/latency_info.h',
         'base/l10n/l10n_font_util.cc',
         'base/l10n/l10n_font_util.h',
         'base/l10n/l10n_util.cc',
         'base/l10n/l10n_util.h',
         'base/l10n/l10n_util_android.h',
         'base/l10n/l10n_util_android.cc',
         'base/l10n/l10n_util_collator.h',
         'base/l10n/l10n_util_mac.h',
         'base/l10n/l10n_util_mac.mm',
+        'base/l10n/l10n_util_plurals.cc',
+        'base/l10n/l10n_util_plurals.h',
         'base/l10n/l10n_util_posix.cc',
         'base/l10n/l10n_util_win.cc',
         'base/l10n/l10n_util_win.h',
         'base/l10n/time_format.cc',
         'base/l10n/time_format.h',
         'base/layout.cc',
         'base/layout.h',
         'base/layout_mac.mm',
         'base/models/button_menu_item_model.cc',
         'base/models/button_menu_item_model.h',
@@ skipping 855 matching lines @@
               'xcode_settings': {
                 'GCC_SYMBOLS_PRIVATE_EXTERN': 'NO',
               },
             }],
           ],
         },
       ],
     }],
   ],
 }