[Mojo-Loading] Implement URLLoader::SetPriority

content/common/url_request_struct_traits.h

+// Copyright 2017 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 CONTENT_COMMON_URL_REQUEST_STRUCT_TRAITS_H_
+#define CONTENT_COMMON_URL_REQUEST_STRUCT_TRAITS_H_
+
+#include "content/common/url_loader.mojom.h"
+#include "mojo/public/cpp/bindings/enum_traits.h"
+#include "net/base/request_priority.h"
+
+namespace mojo {
+
+template <>
+struct EnumTraits<content::mojom::RequestPriority, net::RequestPriority> {
+  static content::mojom::RequestPriority ToMojom(net::RequestPriority priority);
+  static bool FromMojom(content::mojom::RequestPriority in,
+                        net::RequestPriority* out);
+};
+
+}  // namespace mojo
+
+#endif  // CONTENT_COMMON_URL_REQUEST_STRUCT_TRAITS_H_