[Chromecast] Add a custom CastMediaClient for Chromecast

chromecast/common/media/cast_media_client.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 CHROMECAST_COMMON_MEDIA_CAST_MEDIA_CLIENT_H_
+#define CHROMECAST_COMMON_MEDIA_CAST_MEDIA_CLIENT_H_
+
+#include "base/lazy_instance.h"
+#include "base/macros.h"
+#include "media/base/media_client.h"
+
+namespace chromecast {
+namespace media {
+
+// Forwards MediaClient::IsSupportedVideoConfig calls to MediaCapabilitiesShlib
+// and the rest of the calls to the default content media client (i.e.
+// content::RenderMediaClient).
+class CastMediaClient : public ::media::MediaClient {
+ public:
+  // Initialize CastMediaClient and SetMediaClient(). Note that the instance
+  // is not exposed because no content code needs to directly access it.
+  static void Initialize();
+
+  // MediaClient implementation
+  void AddKeySystemsInfoForUMA(std::vector<::media::KeySystemInfoForUMA>*
+                                   key_systems_info_for_uma) override;
+  bool IsKeySystemsUpdateNeeded() override;
+  void AddSupportedKeySystems(
+      std::vector<std::unique_ptr<::media::KeySystemProperties>>*
+          key_systems_properties) override;
+  void RecordRapporURL(const std::string& metric, const GURL& url) override;
+  bool IsSupportedVideoConfig(::media::VideoCodec codec,
+                              ::media::VideoCodecProfile profile,
+                              int level) override;
+
+ private:
+  friend struct base::DefaultLazyInstanceTraits<CastMediaClient>;
+
+  CastMediaClient();
+  ~CastMediaClient() override;
+
+  ::media::MediaClient* content_media_client_;
+
+  DISALLOW_COPY_AND_ASSIGN(CastMediaClient);
+};
+
+}  // namespace media
+}  // namespace chromecast
+
+#endif  // CHROMECAST_COMMON_MEDIA_CAST_MEDIA_CLIENT_H_