Migrating MediaSession messages to mojo

content/browser/media/android/media_session_service.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 CONTENT_BROWSER_MEDIA_ANDROID_MEDIA_SESSION_SERVICE_H_
+#define CONTENT_BROWSER_MEDIA_ANDROID_MEDIA_SESSION_SERVICE_H_
+
+#include "mojo/public/cpp/bindings/binding.h"
+#include "third_party/WebKit/public/platform/modules/mediasession/media_session.mojom.h"
+
+namespace content {
+
+class RenderFrameHost;
+
+class MediaSessionService

[jam, 2016/10/04 16:03:46]

nit: MediaSessionImpl is the convention, no need to add Service at end

[Zhiqiang Zhang (Slow), 2016/10/06 11:06:31]

I'm using `MediaSessionService` in mojo and `MediaSessionServiceImpl` in
content. The reason is that there's already `content::MediaSession` which means
a different thing.

+    : public NON_EXPORTED_BASE(blink::mojom::MediaSession) {

[jam, 2016/10/04 16:03:46]

I don't think you need the NON_EXPORTED_BASE since this class isn't exported

[Zhiqiang Zhang (Slow), 2016/10/06 11:06:31]

Done.

+ public:
+  ~MediaSessionService() override;
+
+  static void Create(RenderFrameHost* render_frame_host,
+                     blink::mojom::MediaSessionRequest request);
+
+ private:
+  explicit MediaSessionService(RenderFrameHost* render_frame_host);
+
+  void SetMetadata(
+      const base::Optional<content::MediaMetadata>& metadata) override;
+
+  void Bind(mojo::InterfaceRequest<blink::mojom::MediaSession> request);
+
+  RenderFrameHost* render_frame_host_;
+
+  // RAII binding of |this| to an MediaSession interface request.
+  // The binding is removed when binding_ is cleared or goes out of scope.
+  std::unique_ptr<mojo::Binding<blink::mojom::MediaSession>> binding_;
+
+  DISALLOW_COPY_AND_ASSIGN(MediaSessionService);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_MEDIA_ANDROID_MEDIA_SESSION_SERVICE_H_