Remove chrome::NOTIFICATION_WEB_DIALOG_SHOWN.

chrome/chrome_browser.gypi

 # 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.
 
 {
   'targets': [
     {
       'target_name': 'browser',
       'type': 'static_library',
@@ skipping 3917 matching lines @@
         'browser/ui/webui/test_chrome_web_ui_controller_factory.h',
         'browser/ui/webui/theme_source.cc',
         'browser/ui/webui/theme_source.h',
         'browser/ui/webui/tracing_ui.cc',
         'browser/ui/webui/tracing_ui.h',
         'browser/ui/webui/uber/uber_ui.cc',
         'browser/ui/webui/uber/uber_ui.h',
         'browser/ui/webui/web_dialog_controller.cc',
         'browser/ui/webui/web_dialog_controller.h',
         'browser/ui/webui/web_dialog_delegate.h',
+        'browser/ui/webui/web_dialog_observer.h',
         'browser/ui/webui/web_dialog_web_contents_delegate.cc',
         'browser/ui/webui/web_dialog_web_contents_delegate.h',
         'browser/ui/webui/web_dialog_ui.cc',
         'browser/ui/webui/web_dialog_ui.h',
         'browser/ui/webui/web_ui_util.cc',
         'browser/ui/webui/web_ui_util.h',
         'browser/ui/window_sizer.cc',
         'browser/ui/window_sizer.h',
         'browser/ui/window_sizer_ash.cc',
         'browser/ui/window_sizer_aura.cc',
@@ skipping 1127 matching lines @@
         'browser/metrics/proto/study.proto',
       ],
       'variables': {
         'proto_in_dir': 'browser/metrics/proto',
         'proto_out_dir': 'chrome/browser/metrics/proto',
       },
       'includes': [ '../build/protoc.gypi' ]
     },
   ],
 }