AndroidOverlay implementation using Dialog.

media/base/routing_token_callback.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 MEDIA_BASE_ROUTING_TOKEN_CALLBACK_H_
+#define MEDIA_BASE_ROUTING_TOKEN_CALLBACK_H_
+
+#include "base/callback.h"
+#include "base/unguessable_token.h"
+
+namespace media {
+
+// Handy callback type to provide a routing token.
+using RoutingTokenCallback =
+    base::Callback<void(const base::UnguessableToken&)>;
+
+}  // namespace media
+
+#endif  // MEDIA_BASE_ANDROID_ROUTING_TOKEN_CALLBACK_H_