Change mojo enums to be scoped enums in the generated C++ bindings.

components/web_view/public/cpp/web_view.cc

 // 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.
 
 #include "components/web_view/public/cpp/web_view.h"
 
 #include <stdint.h>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 18 matching lines @@
       GetProxy(&client);
   binding_.Bind(std::move(client_request));
 
   mojom::WebViewFactoryPtr factory;
   app->ConnectToService("mojo:web_view", &factory);
   factory->CreateWebView(std::move(client), GetProxy(&web_view_));
 
   mus::mojom::WindowTreeClientPtr window_tree_client;
   web_view_->GetWindowTreeClient(GetProxy(&window_tree_client));
   window->Embed(std::move(window_tree_client),
-                mus::mojom::WindowTree::ACCESS_POLICY_EMBED_ROOT,
+                mus::mojom::WindowTree::kAccessPolicyEmbedRoot,
                 base::Bind(&OnEmbed));
 }
 
 }  // namespace web_view