MD Settings: break SettingsPageUIHandler to its own file

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

 // Copyright 2016 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_CERTIFICATES_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_SETTINGS_CERTIFICATES_HANDLER_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/task/cancelable_task_tracker.h"
 #include "chrome/browser/certificate_manager_model.h"
-#include "chrome/browser/ui/webui/settings/md_settings_ui.h"
+#include "chrome/browser/ui/webui/settings/settings_page_ui_handler.h"
 #include "net/cert/nss_cert_database.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/shell_dialogs/select_file_dialog.h"
 
 namespace settings {
 
 class CertIdMap;
 class FileAccessProvider;
 
 class CertificatesHandler
@@ skipping 165 matching lines @@
   scoped_ptr<CertIdMap> cert_id_map_;
 
   base::WeakPtrFactory<CertificatesHandler> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(CertificatesHandler);
 };
 
 }  // namespace settings
 
 #endif  // CHROME_BROWSER_UI_WEBUI_SETTINGS_CERTIFICATES_HANDLER_H_