Remove balloon notification code. The last user was the Linux GTK port but that's deleted now.

chrome/chrome_browser.gypi

 # Copyright 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.
 
 {
   'targets': [
     {
       'target_name': 'browser',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
@@ skipping 1351 matching lines @@
         'browser/net/url_info.h',
         'browser/network_time/navigation_time_helper.cc',
         'browser/network_time/navigation_time_helper.h',
         'browser/network_time/network_time.h',
         'browser/network_time/network_time_service.cc',
         'browser/network_time/network_time_service.h',
         'browser/network_time/network_time_service_factory.cc',
         'browser/network_time/network_time_service_factory.h',
         'browser/network_time/network_time_tracker.cc',
         'browser/network_time/network_time_tracker.h',
-        'browser/notifications/balloon.cc',
-        'browser/notifications/balloon.h',
-        'browser/notifications/balloon_collection.cc',
-        'browser/notifications/balloon_collection.h',
-        'browser/notifications/balloon_collection_base.cc',
-        'browser/notifications/balloon_collection_base.h',
-        'browser/notifications/balloon_collection_impl.cc',
-        'browser/notifications/balloon_collection_impl.h',
-        'browser/notifications/balloon_host.cc',
-        'browser/notifications/balloon_host.h',
-        'browser/notifications/balloon_notification_ui_manager.cc',
-        'browser/notifications/balloon_notification_ui_manager.h',
         'browser/notifications/desktop_notification_service.cc',
         'browser/notifications/desktop_notification_service.h',
         'browser/notifications/desktop_notification_service_factory.cc',
         'browser/notifications/desktop_notification_service_factory.h',
         'browser/notifications/desktop_notification_service_win.cc',
         'browser/notifications/extension_welcome_notification.cc',
         'browser/notifications/extension_welcome_notification.h',
-        'browser/notifications/fake_balloon_view.cc',
-        'browser/notifications/fake_balloon_view.h',
         'browser/notifications/message_center_notification_manager.cc',
         'browser/notifications/message_center_notification_manager.h',
         'browser/notifications/message_center_notification_manager_win.cc',
         'browser/notifications/message_center_settings_controller.cc',
         'browser/notifications/message_center_settings_controller.h',
         'browser/notifications/message_center_stats_collector.cc',
         'browser/notifications/message_center_stats_collector.h',
         'browser/notifications/notification.cc',
         'browser/notifications/notification.h',
         'browser/notifications/screen_lock_notification_blocker.cc',
         'browser/notifications/screen_lock_notification_blocker.h',
         'browser/notifications/fullscreen_notification_blocker.cc',
         'browser/notifications/fullscreen_notification_blocker.h',
         'browser/notifications/login_state_notification_blocker_chromeos.cc',
         'browser/notifications/login_state_notification_blocker_chromeos.h',
         'browser/notifications/notification_delegate.cc',
         'browser/notifications/notification_delegate.h',
         'browser/notifications/notification_object_proxy.cc',
         'browser/notifications/notification_object_proxy.h',
-        'browser/notifications/notification_options_menu_model.cc',
-        'browser/notifications/notification_options_menu_model.h',
-        'browser/notifications/notification_prefs_manager.cc',
-        'browser/notifications/notification_prefs_manager.h',
         'browser/notifications/notification_system_observer.cc',
         'browser/notifications/notification_system_observer.h',
         'browser/notifications/notification_ui_manager.cc',
         'browser/notifications/notification_ui_manager.h',
         'browser/notifications/sync_notifier/chrome_notifier_delegate.cc',
         'browser/notifications/sync_notifier/chrome_notifier_delegate.h',
         'browser/notifications/sync_notifier/chrome_notifier_service.cc',
         'browser/notifications/sync_notifier/chrome_notifier_service.h',
         'browser/notifications/sync_notifier/chrome_notifier_service_factory.cc',
         'browser/notifications/sync_notifier/chrome_notifier_service_factory.h',
@@ skipping 2386 matching lines @@
             'package_name': 'org/chromium/chrome/browser',
             'template_deps': ['browser/android/tab_load_status.h'],
           },
           'includes': [ '../build/android/java_cpp_template.gypi' ],
         },
       ],
      },
     ],
   ],
 }