[Mac] Add a confirm to quit experiment to about:flags.

chrome/chrome_tests.gypi

 # Copyright (c) 2010 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' : {
     'pyautolib_sources': [
       'app/chrome_dll_resource.h',
       'common/pref_names.cc',
       'common/pref_names.h',
@@ skipping 1120 matching lines @@
         'browser/cocoa/bubble_view_unittest.mm',
         'browser/cocoa/bug_report_window_controller_unittest.mm',
         'browser/cocoa/chrome_browser_window_unittest.mm',
         'browser/cocoa/chrome_event_processing_window_unittest.mm',
         'browser/cocoa/clear_browsing_data_controller_unittest.mm',
         'browser/cocoa/clickhold_button_cell_unittest.mm',
         'browser/cocoa/cocoa_test_helper.h',
         'browser/cocoa/cocoa_test_helper.mm',
         'browser/cocoa/collected_cookies_mac_unittest.mm',
         'browser/cocoa/command_observer_bridge_unittest.mm',
+        'browser/cocoa/confirm_quit_panel_controller_unittest.mm',
         'browser/cocoa/content_exceptions_window_controller_unittest.mm',
         'browser/cocoa/content_setting_bubble_cocoa_unittest.mm',
         'browser/cocoa/content_settings_dialog_controller_unittest.mm',
         'browser/cocoa/cookie_details_unittest.mm',
         'browser/cocoa/cookie_details_view_controller_unittest.mm',
         'browser/cocoa/custom_home_pages_model_unittest.mm',
         'browser/cocoa/delayedmenu_button_unittest.mm',
         'browser/cocoa/download/download_item_button_unittest.mm',
         'browser/cocoa/download/download_shelf_mac_unittest.mm',
         'browser/cocoa/download/download_shelf_view_unittest.mm',
@@ skipping 2176 matching lines @@
       ]
     }],  # 'coverage!=0'
   ],  # 'conditions'
 }
 
 # Local Variables:
 # tab-width:2
 # indent-tabs-mode:nil
 # End:
 # vim: set expandtab tabstop=2 shiftwidth=2: