Remove unused typemap includes from generated C++ mojo bindings.

chrome/browser/notifications/non_persistent_notification_handler.cc

 // 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.
 
 #include "chrome/browser/notifications/non_persistent_notification_handler.h"
 
+#include "base/strings/nullable_string16.h"
 #include "chrome/browser/notifications/notification_delegate.h"
 #include "chrome/browser/notifications/platform_notification_service_impl.h"
 
 NonPersistentNotificationHandler::NonPersistentNotificationHandler() {}
 NonPersistentNotificationHandler::~NonPersistentNotificationHandler() {}
 
 void NonPersistentNotificationHandler::OnClose(
     Profile* profile,
     const std::string& origin,
     const std::string& notification_id,
@@ skipping 23 matching lines @@
   NotificationCommon::OpenNotificationSettings(profile);
 }
 
 void NonPersistentNotificationHandler::RegisterNotification(
     const std::string& notification_id,
     NotificationDelegate* delegate) {
   DCHECK_EQ(notifications_.count(notification_id), 0u);
   notifications_[notification_id] =
       scoped_refptr<NotificationDelegate>(delegate);
 }