MD Settings: break SettingsPageUIHandler to its own file

chrome/browser/ui/webui/settings/people_handler.h

 // Copyright 2015 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_SETTINGS_PEOPLE_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_SETTINGS_PEOPLE_HANDLER_H_
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/scoped_observer.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/timer/timer.h"
 #include "build/build_config.h"
 #include "chrome/browser/profiles/profile_attributes_storage.h"
 #include "chrome/browser/sync/sync_startup_tracker.h"
-#include "chrome/browser/ui/webui/settings/md_settings_ui.h"
+#include "chrome/browser/ui/webui/settings/settings_page_ui_handler.h"
 #include "chrome/browser/ui/webui/signin/login_ui_service.h"
 #include "components/prefs/pref_change_registrar.h"
 #include "components/signin/core/browser/signin_manager_base.h"
 #include "components/sync_driver/sync_service_observer.h"
 
 #if defined(OS_CHROMEOS)
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #endif
 
@@ skipping 192 matching lines @@
 
   // Manages observer lifetime.
   ScopedObserver<ProfileSyncService, PeopleHandler> sync_service_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(PeopleHandler);
 };
 
 }  // namespace settings
 
 #endif  // CHROME_BROWSER_UI_WEBUI_SETTINGS_PEOPLE_HANDLER_H_